Papers - TATAMI Junichi
about 639-
Correlation analysis of granulation condition, granule properties and green density of alumina ceramics fabricated by spray freeze granulation drying
Chung, Y; Kondo, N; Kita, K; Hotta, M; Tatami, J; Kawaguchi, S
Advanced Powder Technology 37 ( 5 ) 105251 2026.5 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effect of PVA saponification degree on internal structural changes in silica slurry during drying
Kuroda, H; Tatami, J; Iijima, M; Takahashi, T
Advanced Powder Technology 37 ( 3 ) 105189 2026.3 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Ultra-high throughput manufacturing process of 3D printed silica glass components with shrinkage ratio control over a wide range
Yamanoi, Y; Yamada, S; Tatami, J; Iijima, M
Chemical Engineering Journal 525 170008 2025.12 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Freezing behaviour and spray freeze granulation drying of silicon nitride slurries prepared from tert-butyl alcohol and cyclohexane solvent mixtures ☆
Yamazaki, R; Tatami, J; Iijima, M; Kawaguchi, S; Kondo, N
Advanced Powder Technology 36 ( 11 ) 105030 2025.11 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effect of coarse-Si-powder addition on the thermal and mechanical properties of sintered reaction-bonded silicon nitride
Shimada, K; Tatami, J
Ceramics International 51 ( 25 ) 44942 - 44951 2025.10 [Reviewed]
Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Internal Structure Observation of an Aged Violin by OCT and THz Imaging
Fukunaga, K; Yamazaki, R; Tatami, J; Takahashi, T; Ito, H; Masuda, S
Journal of Infrared Millimeter And Terahertz Waves 46 ( 10 ) 68 2025.9 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effects of compositions on grain-boundary strength of α/β-SiAlON ceramics determined by microcantilever bending tests
Masuda, Y; Ohji, T; Takahashi, T; Iijima, M; Tatami, J
Ceramics International 51 ( 21 ) 35214 - 35217 2025.9 [Reviewed]
Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Transparent photocurable Pickering emulsion for improving printing resolution of porous silica components
Tsutaki, S; Tatami, J; Iijima, M
Journal of The Ceramic Society of Japan 133 ( 8 ) 444 - 449 2025.8 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microscale rising R-curve behavior of silicon nitride ceramics
Saito, T; Ohji, T; Takahashi, T; Iijima, M; Tatami, J
Journal of The American Ceramic Society 108 ( 7 ) 2025.7 [Reviewed]
Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Grain and grain boundary strength of silicon nitride ceramics with different thermal conductivities and microstructures
Shimada, K; Tatami, J
Ceramics International 51 ( 17 ) 24306 - 24313 2025.7 [Reviewed]
Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Sustainable 3D Printing of Transparent SiO2 Glass Components by a Photocurable Aqueous Suspension Design
Ma, BH; Yahagi, T; Tatami, J; Iijima, M
Acs Sustainable Chemistry & Engineering 13 ( 24 ) 9044 - 9052 2025.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Mechanical Properties of Silicon Nitride Ceramics Determined by Microcantilever Tests - A Comprehensive Overview
Tatami, J; Ohji, T
Transactions of The Indian Ceramic Society 84 ( 1 ) 20 - 28 2025.1 [Reviewed]
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Joint Work
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粒子間光架橋性ピッカリングエマルションの設計とセラミックス多孔体の造形プロセスへの応用
飯島 志行, 山野井 慶彦, 蔦木 将吾, 多々見 純一
粉体工学会誌 62 ( 1 ) 25 - 30 2025.1 [Reviewed] [Invited]
Authorship：Last author Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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Lowering compaction pressure and sintering temperature of alumina using spray freeze granulation dried granules
Kondo, N; Shimamura, A; Hotta, M; Tatami, J; Kawaguchi, S
Journal of The Ceramic Society of Japan 133 ( 1 ) 34 - 38 2025.1 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Crack suppression during debinding of photocured green bodies comprising interparticle polymer cross-links with silane oligomers
Yamada, S; Sakamoto, N; Tatami, J ; Iijima, M
ADVANCED POWDER TECHNOLOGY 35 ( 11 ) 104663 2024.11 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Processing-structure-microscale properties of silicon nitride
Ohji Tatsuki, Tatami Junichi
Ceramics International 50 ( 19, Part C ) 37282 - 37290 2024.10 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Joint Work
This paper presents an overview of recent works on microscale mechanical and other properties of silicon nitride (Si3N4) determined by microcantilever bending tests and their relationships with the processing and microstructures. We first focus on deformation behaviors and fracture strength of Si3N4 single crystals. β-Si3N4 single crystals are plastically deformed at room temperature under high bending stress, and the yield stress depends on the crystal orientation. The critical resolved share stress of the primary slip system is determined to be below 1.5 GPa from the yield stress. Next, we address microscale mechanical properties of Si3N4 polycrystalline ceramics. Emphasis is placed on their grain-boundary strength or toughness in conjunction with intergranular glassy film (IGF) which is determined by processing parameters such as sintering additives. Assessment is made on two cases of fractures at the IGF-grain interface and that within the IGF, and in each of the cases, effects of rare earth oxide additives are discussed. In Si3N4 ceramics doped with Al2O3, β-SiAlON layer forming on β-Si3N4 grains enhances the microscale grain-boundary strength. Finally, we shed light on microscale property-degradation behaviors of Si3N4 ceramics, including the deterioration due to the contact with molten Al and the corrosion in sulfuric acid solution. The variation of the microscale properties appears in very short periods compared to the macroscale approaches, demonstrating the advantage in terms of rapid assessment of time-dependent degradation behaviors.
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Yahagi Tsukaho, Ohji Tatsuki, Yamaguchi Hiroshi, Takahashi Takuma, Nakano Hiromi, Iijima Motoyuki, … Show more authors
Yahagi Tsukaho, Ohji Tatsuki, Yamaguchi Hiroshi, Takahashi Takuma, Nakano Hiromi, Iijima Motoyuki, Tatami Junichi Hide authors
ADVANCED ENGINEERING MATERIALS 26 ( 18 ) 2024.9 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
In this study, the deformation behaviors and mechanical properties of 4H-SiC single crystals are investigated using microcantilever beam specimens with two different sizes, A and B (A < B). Tensile stress is applied along <1120> direction. Plastic deformation, or nonlinearity, is observed in the stress–strain curves, and yield stress, or proportional limit, coincides between the two specimens at ≈25 ± 2 GPa. Scanning transmission electron microscopy and transmission electron microscopy studies show that the plastic deformation is due to dislocation activities; multiple-dislocation pileup areas are observed in both the specimens. Assuming {1100}/<1120> prismatic slip which most plausibly occurs in the <1120> stress application, the critical resolved shar stress is estimated to be 10.9 GPa, which agrees well with the previous studies. Measured fracture strength is 41.9 ± 2.8 and 33.5 ± 2.4 GPa for the A and B, respectively. Dislocation–fracture relationship is discussed on the basis of dislocation-based fracture mechanics, etc. It is suggested that cracks form within the multiple-dislocation pileup area, by interaction with dislocation pileups, and act as fracture origins. A's strength is close to an ideal tensile strength of 4H-SiC in the <1120> direction, 47–55 GPa.
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Effects of rare-earth oxides on grain boundary strength of silicon nitride ceramics
Matsuura Komaki, Ohji Tatsuki, Takahashi Takuma, Iijima Motoyuki, Tatami Junichi
Journal of the European Ceramic Society 44 ( 14 ) 2024.6 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Joint Work
This study investigates the grain boundary (GB) strengths for Si3N4 ceramics doped with 3 wt% RE2O3 (RE = Y, La, or Lu) and 7 wt% MgO, using microcantilever beam specimens having different misorientation angles of the two adjacent grains. The measured strengths are so high that they are comparable to the theoretical strength of the intergranular glassy film (IGF). They are also widely scattered with a Weibull modulus of 3.0. The strength depends on the type of RE2O3 and increases in order of Y<La<Lu. It is suggested that the fracture occurs from the IGF/Si3N4 interfaces rather than within the IGF, and that O anions, which reside within the IGF and do not dissolve into the β-Si3N4 crystal lattice because of the high cationic field strength, reduce the IGF/grain interface strength. The GB strength also little depends on the misorientation angles, which is discussed in relation with the IGF accommodation ability of mismatch.
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Micro-scale mechanical properties of surface layer in ion-exchanged glass
Fujita, S; Ohji, T; Yahagi, T; Iijima, M; Tatami, J
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 107 ( 6 ) 3666 - 3672 2024.6 [Reviewed]
DOI Web of Science CiNii Research Repository
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:title>Abstract</jats:title><jats:p>Today, ion‐exchanged or chemically strengthened glass is ubiquitously used all over the world, typically for scratch‐free display cover of personal mobile phones. It has been known that the strengthening is due to developments of high compressive stress in the surface layer by its internally constrained dilation . We investigated micro‐scale mechanical properties of the surface layer itself of a Na<jats:sup>+</jats:sup>‐to‐K<jats:sup>+</jats:sup> ion‐exchanged soda lime silicate glass, revealing that the strength of the layer increased nearly 40% by the ion‐exchange with little compression effect from the interior. The fracture toughness, however, was comparable before and after the ion‐exchange, indicating that the ion‐exchange reduces the crack size of the fracture origin. Theoretical estimates of fracture surface energies verified the measured fracture toughness. It was presumed that the observed crack‐size reduction is due to crack healing effects enhanced by the ion‐exchange.</jats:p>
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Validation study on a coarse-grained DEM-CFD simulation in a bead mill
Tsunazawa, Y; Soma, N; Iijima, M; Tatami, J; Mori, T; Sakai, M
POWDER TECHNOLOGY 440 119743 2024.5 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Digital light processing printing of porous ceramics using interparticle photo-cross-linkable Pickering emulsions
Tsutaki, S; Yamanoi, Y; Tatami, J; Iijima, M
ADVANCED POWDER TECHNOLOGY 35 ( 5 ) 104410 2024.5 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Scintillation properties of transparent Lu-α-SiAlON:Ce3+ ceramics
K. Aminaka, J. Tatami, M. Iijima, A. Ito, S. Matsumoto, T. Takahashi. T. Ohji
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY - 2024.4 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:title>Abstract</jats:title><jats:p>The high durability under harsh environment including high temperature, high humidity, and high radiation is required for scintillators used for decommissioning of nuclear facilities and radiation monitoring in nuclear fusion reactors. α‐SiAlON ceramics are highly potential for such scintillators because of their thermal and mechanical durability and luminescence corresponding to doped rare‐earth ion. In this study, scintillation properties of transparent Lu‐α‐SiAlON:Ce<jats:sup>3+</jats:sup> ceramics were investigated for the first time. Lu‐α‐SiAlON:Ce<jats:sup>3+</jats:sup> showed the scintillation responses to α‐rays and X‐rays. The α‐rays‐induced scintillation decay curve consists of two components whose decay time are 48 and 652 ns. The faster decay component most presumably results from 4f‐5d transition of Ce<jats:sup>3+</jats:sup>, whereas the origin of the slower one is unclear but may be defects in α‐SiAlON. The light yield of the Lu‐α‐SiAlON:Ce<jats:sup>3+</jats:sup> ceramics was 1300 photons 5.5 MeV<jats:sup>−1</jats:sup>.</jats:p>
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Compactability and sinterability of alumina granules made by spray freeze granulation drying and spray drying
N. Kondo, A. Shimamura, M. Hotta, J. Tatami, S. Kawaguchi
Journal of the Ceramic Society of Japan 132 ( 4 ) 145 - 151 2024.4 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effect of Graphene Coating by Mechanical Treatment on Water Resistance of Aluminum Nitride Particles
61 154 - 159 2024.3 [Reviewed]
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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Muramoto, M; Tatami, J; Iijima, M; Matsui, K; Yahagi, T; Takahashi, T; Nakano, H; Ohji, T
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 44 ( 2 ) 1061 - 1069 2024.2 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Micro- and macro-scale strength properties of c-axis aligned hydroxyapatite ceramics
Y. Otsuka, J. Tatami, I. Yamamoto, M. Iijima, T. Ohji
Ceramics International 49 ( 24 ) 40158 - 40165 2023.12 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microscopic mechanical properties of silicon nitride ceramics corroded in sulfuric acid solution
J. Tatami, M. Uda, T. Takahashi, T. Yahagi, M. Iijima, K. Matsui, T. Ohji, H. Nakano
Journal of the European Ceramic Society 44 ( 9 ) 5415 - 5421 2023.11 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Y. Yamanoi, J. Tatami, M. Iijima
Advanced powder technology 34 ( 12 ) 104240 2023.10 [Reviewed]
DOI Web of Science CiNii Research Repository
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Joint Work
This study aims to investigate the effects of particle surface structures of interparticle photo-cross -linkable w/o Pickering emulsions, designed for the rapid manufacturing of porous ceramic components, on their microstructures, light-curing behaviors, and moldability. The emulsions were designed by mixing SiO2/toluene suspensions stabilized by functional polyethyleneimine (PEI), which was partially complexed with oleic acid (OA) in various ratios (15-50 mol% to total EI units), small quantities of multifunctional acrylate (MA), photo-radical initiator, and water. When the OA content was low (15 mol%), a Pickering emulsion was produced that had a lower size distribution of the dispersed phase than the emulsions obtained when the OA content was high. Additionally, the successful shaping of porous SiO2 bodies by in-situ photocuring of the Pickering emulsion in a silicone mold followed by drying was achieved when the OA content was low. However, severe structural collapse of photocured bodies was observed during drying when the OA content was high (30 and 50 mol%). The higher quantities of reactive amines present on the particle surface played an important role in ensuring interparticle photo-cross-linking, maintaining the structure of photocured bodies against capillary forces during drying.(c) 2023 The Society of Powder Technology Japan. Published by Elsevier BV and The Society of Powder Technology Japan. All rights reserved.
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F. Ito, T. Honda, H. Komuro, F. Yoshikawa, J. Tatami, M. Iijima
Powder Technology 423 118473 2023.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Joint Work
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Achieving Transparent SiAlON Based on Elaborate Powder Process
TATAMI Junichi, AMINAKA Kohei
Hosokawa Powder Technology Foundation ANNUAL REPORT 30 ( 0 ) 99 - 103 2023.5
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Hosokawa Powder Technology Foundation Joint Work
<p>Owing to the growing demand for high power optical devices, the durable transparent materials with fluorescence are demanded. In this study, we focused on α-SiAlON ceramics, which have been developed as structural materials by taking advantage of their high thermal and mechanical properties, and realized blue light-emitting transparent Lu-α-SiAlON:Ce<sup>3+</sup> ceramics. A higher Ce concentration resulted in a red shift of the fluorescence. Furthermore, using finer raw powders of rare-earth oxide improved the in-line transmittance of Lu-α-SiAlON:Ce<sup>3+</sup> ceramics.</p>
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Deformation behaviors and fracture strength of β-Si3N4 single crystals
Mami Tanabe, Junichi Tatami, Motoyuki Iijima, Tsukaho Yahagi, Takuma Takahashi, Hiromi Nakano, Tats … Show more authors
Mami Tanabe, Junichi Tatami, Motoyuki Iijima, Tsukaho Yahagi, Takuma Takahashi, Hiromi Nakano, Tatsuki Ohji Hide authors
Journal of the American Ceramic Society 106 ( 9 ) 5431 - 5439 2023.4 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Single Work
<jats:title>Abstract</jats:title><jats:p>In this study, the yield stress and fracture strength of ‐Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> single crystals were directly measured by bending tests of microcantilever beam specimens that were prepared by a focused ion beam method. The ‐Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> single crystals were plastically deformed at room temperature under high bending stress, and the yield stress depended on the crystal orientation. Transmission electron microscopy observation of the specimens after bending tests indicates that the plastic deformation resulted from dislocations in the primary slip system <0001>, and the critical resolved shear stress of this slip system determined from the yield stress was 1.34 GPa. The fracture strength of ‐Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> single crystals ranged approximately up to 20 GPa, depending on the crystal orientation as with the yield stress. The fracture behavior of ‐Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> single crystals was discussed in terms of the accumulation of dislocations.</jats:p>
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Selecting an appropriate binder to prepare alumina granules via spray freeze granulation drying
N. Kondo, A. Shimamura, M. Hotta, J. Tatami, S. Kawaguchi
Journal of the Ceramic Society of Japan 131 ( 4 ) 106 - 111 2023.4 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Hiromasa Kuroda, Junichi Tatami, Motoyuki Iijima, Motoyuki, Takuma Takahashi
Journal of the Ceramic Society of Japan 131 ( 3 ) 37 - 41 2023.3 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Single Work
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Otsuka Yuki, Yamamoto Isao, Iijima Motoyuki, Tatami Junichi
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY 20 ( 2 ) 708 - 717 2023.3 [Reviewed]
DOI Web of Science CiNii Research
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:title>Abstract</jats:title><jats:p>Controlling the crystal orientation of hydroxyapatite, an inorganic material that is a major component of human hard tissues is important to fabricate better artificial bones and artificial tooth roots. To obtain highly oriented hydroxyapatite ceramics under a strong magnetic field, a good dispersion of the raw materials in the slurry must be obtained. This study investigates the effect of wet‐jet milling of a slurry on the orientation of hydroxyapatite ceramics fabricated using a strong magnetic field. Although the prolonged ball milling with ZrO<jats:sub>2</jats:sub> balls of the raw powder fractures the primary particles of hydroxyapatite, wet‐jet milling is used to successfully pulverize agglomerated hydroxyapatite raw powder without changing the morphology of the primary particles. Evidently, ceramics with a highly oriented <jats:italic>c</jats:italic>‐axis of hydroxyapatite are obtained by molding the wet‐jet milled slurry in a strong rotating magnetic field. They exhibit anisotropy in fracture toughness, and the fracture toughness calculated from the crack length perpendicular to the rotating axis is higher than that calculated from the crack length parallel to it. Furthermore, these values are higher than those of randomly oriented hydroxyapatite ceramics, which may be owing to the crystal orientation dependence of the fracture toughness of the hydroxyapatite grains and grain boundaries.</jats:p>
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M. Minami, J. Tatami, M. iijima, T. Takahashi, T. Ohji
Ceramics International 49 ( 10 ) 15387 - 15394 2023.1 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
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Otsuka Yuki, Yamamoto Isao, Iijima Motoyuki, Tatami Junichi
Ceramics International 48 ( 20 ) 29669 - 29675 2022.8 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Science Ltd. Joint Work
Understanding and controlling the anisotropic sintering shrinkage behavior of the green body in the strong magnetic field molding technique bring out the superior functions of ceramics. This study aimed to elucidate the sintering behavior of green bodies molded under a strong magnetic field using the master sintering curve (MSC) theory. Green bodies were prepared to obtain MSCs in the directions perpendicular and parallel to the applied magnetic field. A unique MSC of the alumina green bodies molded with and without a magnetic field was ob-tained using sintering shrinkage ratio estimated by various heating rates. The apparent activation energy of sintering in the direction perpendicular and parallel to the applied magnetic field was 663 kJ/mol, independent of the measured direction, which is higher than that without an applied magnetic field (562 kJ/mol). The (0001) planes of the sintered body obtained from the green body molded in the magnetic field were oriented perpen-dicular to the magnetic field, whereas the samples without a magnetic field were randomly oriented. Conse-quently, we found that the grain boundaries with high consistency in the sample applied to a magnetic field should increase the apparent activation energy because of its grain orientation.
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Transparency and Photoluminescence of Gas-Pressure Sintered Lu-alpha-SiAlON:Ce3+ Ceramics
Aminaka Kohei, Tatami Junichi, Iijima Motoyuki, Takahashi Takuma
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY 11 ( 7 ) 076001 2022.7 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：The Electrochemical Society Joint Work
<jats:p>Owing to the growing demand for high power optical devices in several fields such as manufacturing, medicine, and communications, the demand for large and transparent inorganic materials capable of emitting multiple colors is increasing. <jats:italic>α</jats:italic>-SiAlON, which has excellent thermal and mechanical properties, is a phosphor that emits blue light because of the doping of Ce<jats:sup>3+</jats:sup>. However, only a few transparent and photoluminescent <jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> ceramics have been developed. In this study, we fabricated transparent <jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> ceramics using a gas-pressure sintering technique utilizing Lu<jats:sup>3+</jats:sup>, which has the smallest ionic radius among the rare-earth ions used to stabilize <jats:italic>α</jats:italic>-SiAlON. The Lu-<jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> ceramics exhibited higher transparency than Y-<jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> because of their finer grain size. The maximum emission wavelength of the Lu-<jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> ceramics was blue shifted relative to that of the Y-<jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> ceramics owing to lattice shrinkage. A lower Ce concentration resulted in higher transparency and a blue shift in the maximum emission wavelength. Furthermore, the in-line transmittance of the gas-pressure sintered Lu-<jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> ceramics using fine raw powders of rare-earth oxides was 50% at 600 nm, which was higher than that of Y-<jats:italic>α</jats:italic>-SiAlON:Ce<jats:sup>3+</jats:sup> ceramics prepared via the same gas-pressure sintering technique followed by hot isostatic pressing.</jats:p>
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Yoshihiko Yamanoi, Junichi Tatami, Motoyuki Iijima
Advanced Powder Technology 33 ( 7 ) 103638 2022.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Single Work
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Ryota Sato, Tsukaho Yahagi, Junichi Tatami, Motoyuki Iijima
ACS Applied Materials & Interfaces 14 ( 14 ) 16445 - 16452 2022.6 [Reviewed]
DOI Web of Science PubMed CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Single Work
The rapid manufacturing of transparent SiO
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Motoyuki Iijima, Ryoya Arita, Yoko Fujishiro, Taichi Furukawa, Shoji Maruo, Junichi Tatami
Advanced Powder Technology 33 ( 4 ) 103533 2022.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Single Work
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Effect of rare-earth oxide additives on transparency and fluorescence of α-SiAlON ceramics
Kohei Aminaka and Junichi Tatami and Motoyuki Iijima and Takuma Takahashi and Tsukaho Yahagi
Ceramics International 48 ( 16 ) 23195 - 23205 2022.5 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Elsevier {BV} Single Work
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Iijima Motoyuki, Taki Naoya, Tatami Junichi
JOURNAL OF COLLOID AND INTERFACE SCIENCE 607 290 - 297 2022.2 [Reviewed]
DOI Web of Science PubMed CiNii Research Repository
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Hypothesis Flow curve measurement is commonly used to characterize the flow behavior of concentrated suspensions. However, dynamic changes in the suspension inner microstructures under highly sheared conditions have not been correctly understood even though they strongly affect the measured shear stress. We hypothesize that the real particle dynamics during shearing could be effectively revealed by a systematic investigation that combines macroscopic flow curve measurements with operando microstructural observation employing an optical coherent tomography (OCT) apparatus and surface interaction measurements with the colloidal probe atomic force microscopy (AFM) method. Experiments The model system was spherical SiO2/toluene suspensions stabilized by polyethyleneimine (PEI) partially complexed with different fatty acids. Inner structures of the suspensions during flow curve measurements were observed by the OCT technique. The surface-surface interactions in toluene were analyzed using the colloidal probe AFM method. Findings Operando OCT observations revealed that during flow curve measurements, the suspensions can have completely different microscopic flow modes depending on the fatty acid species complexed to PEI and the solid concentrations. These microscopic flow modes could not be recognized using the typical flow curve measurements alone. The different flow modes can be explained by surface interactions measured by the colloidal probe AFM method.
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Electrical resistivity of Si3N4 ceramics with Yb2O3 additive
Tsukaho Yahagi and Daisuke Kawai and Takuma Takahashi and Motoyuki Iijima and Junichi Tatami
Journal of the American Ceramic Society 105 ( 3 ) 2046 - 2057 2021.11 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:title>Abstract</jats:title><jats:p>Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics with excellent mechanical properties are used for heat dissipation substrates and so on. In order to improve their reliability and expand their application fields, it is desirable to understand and control the electrical properties of Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics. In this study, the electrical resistivity of Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics with Yb<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> additive was investigated by applying various voltages at temperatures ranging from 25°C to 300°C. When Yb<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> was added as a sintering aid to Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics, a crystalline J‐phase (Yb<jats:sub>4</jats:sub>Si<jats:sub>2</jats:sub>O<jats:sub>7</jats:sub>N<jats:sub>2</jats:sub>) was formed and their electrical resistivity was significantly lower than that of Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> additive. The electrical resistivity of the Yb<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐added ceramics decreased with an increase in temperature and applied voltage. Yb existed in multiple valence states, Yb<jats:sup>2+</jats:sup> and Yb<jats:sup>3+</jats:sup>, in the Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics and the decrease in the electrical resistivity can be attributed hopping conduction through the J‐phase. The J‐phase in the Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics was observed to be continuous, and percolation analysis suggested that the J‐phase formed an infinite cluster. Therefore, the decrease in the electrical resistivity of the Yb<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐added Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics was found mainly to result from the formation of an infinite cluster of J‐phase, which exhibits hopping conduction.</jats:p>
Other Link： https://doi.org/10.1111/jace.18211
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Ceramic Substrate for Power Devices
Tatami Junichi
Journal of The Japan Institute of Electronics Packaging 24 ( 7 ) 680 - 683 2021.11
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Electronics Packaging Single Work
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Takuma Takahashi and Fumika Sakamoto and Junichi Tatami and Motoyuki Iijima
International Journal of Applied Ceramic Technology 19 ( 2 ) 1171 - 1179 2021.9 [Reviewed] [Invited]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:title>Abstract</jats:title><jats:p>In situ observation of sintering of ceramics is important to understand the sintering behavior, including the development of internal structures, and to fabricate ceramics with superior properties. However, there has been no studies thus far on high‐speed in situ observation of the internal structure of green and sintered bodies at high temperatures with micrometer‐scale resolution. Here, we applied swept‐source optical coherence tomography (OCT) to observe the evolution of the internal structure in Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> green bodies during sintering. In situ OCT observations revealed that internal structure changes during sintering, such as the development of density distribution and growth of coarser pores. We could also obtain the sintering shrinkage ratio and relative density from the OCT images. The OCT observation of the internal structure during sintering of green bodies with added or stacked granules of different primary particle sizes confirmed that inhomogeneous regions developed as the densification progressed at high temperatures. These results indicate that in situ observation of the sintering behavior of ceramic green bodies using swept‐source OCT is a novel technique that facilitates real‐time observation of the evolution of the internal structure during sintering.</jats:p>
Other Link： https://doi.org/10.1111/ijac.13909
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Simulation of sintering ceramics based on Master Sintering Curve
NATSUMEDA Chikako, MATSUI Kazumi, TATAMI Junichi, YAMADA Takahiro
Transactions of the JSME (in Japanese) 87 ( 902 ) 21-00237 - 21-00237 2021.9 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Society of Mechanical Engineers Joint Work
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Transparent Y-α SiAlON:Ce3+ Ceramics Fabricated by Low-Temperature Liquid Phase Sintering Technique
Takuma Takahashi and Yuki Sano and Junichi Tatami and Motoyuki Iijima and Masahiro Yokouchi
ECS Journal of Solid State Science and Technology 10 ( 8 ) 086008 2021.8 [Reviewed] [Invited]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Electrochemical Society Joint Work
<jats:p>As the output of solid-state lighting and light sources increases, the demand for transparent phosphor inorganic plates with excellent heat resistance is increasing. It is known that <jats:italic>α</jats:italic>-SiAlON, which has excellent heat resistance as engineering ceramics, shows photoluminescence by stabilized ions, but it is not possible to obtain <jats:italic>α</jats:italic>-SiAlON bulk single crystals. In this study, we fabricated transparent Y-<jats:italic>α</jats:italic> SiAlON:Ce<jats:sup>3+</jats:sup> ceramics for use as wave conversion materials for high-power solid-state semiconductor light sources. For this purpose, gas pressure sintering, followed by hot isostatic pressing at lower temperatures, were carried out using homogeneous and dense green bodies. In particular, cyclic cold isostatic pressing increased the density and homogeneity of the green body, which promoted the densification at lower temperatures and the efficient disappearance of pores during sintering. As a result of the suppression of grain growth by low-temperature densification, Y-<jats:italic>α</jats:italic> SiAlON:Ce<jats:sup>3+</jats:sup> ceramics with high in-line transmittance were successfully obtained. The transparent Y-<jats:italic>α</jats:italic> SiAlON:Ce<jats:sup>3+</jats:sup> ceramics exhibited photoluminescence due to the 5d-4f transition of Ce<jats:sup>3+</jats:sup>. The peak wavelength of the emission intensity depended on the concentration of Ce<jats:sup>3+</jats:sup>, and the luminescence color was in the range of blue to blue-green.</jats:p>
Other Link： https://doi.org/10.1149/2162-8777/ac1e6f
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Kitamura Shoma, Iijima Motoyuki, Tatami Junichi, Fuke Tsubasa, Hinotsu Takashi, Sato Kimitaka
ACS APPLIED MATERIALS & INTERFACES 13 ( 11 ) 13705 - 13713 2021.3 [Reviewed]
DOI Web of Science PubMed CiNii Research
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work
Ag nanowire suspensions are one of the indispensable materials in the design and fabrication of flexible transparent conductive films. Although the required properties of Ag nanowire films, such as their high transparency, low haze, low contact resistance, and suppression of yellowing, are strongly related to the nanowire surface phenomena, approaches for the surface modification of polyol-synthesized Ag nanowires have rarely been reported. Here, we report the design of a polymer ligand and surface modification of Ag nanowires with the designed polymer to obtain color-tunable transparent conductive films through a simple casting and drying process. In this approach, we synthesized a series of functional polymer ligands by partially grafting polyethyleneimine (PEI) with polyethylene glycol (PEG) chains (PEI-mPEG). The amine sites in PEI-mPEG were designed to act as adsorption sites as well as anchoring sites for an anionic blue dye for suppressing the yellow color tone of Ag nanowires. On the other hand, the PEG chains were designed to maintain the stability of the Ag nanowires in aqueous suspensions and to suppress corrosion of Ag nanowires, which is enhanced by the amine groups of PEI. The effect of the grafting ratio of PEG chains on PEI on the ligand-exchange behavior of the Ag nanowires, their dispersion stability in aqueous inks, and final film properties were investigated systematically. Furthermore, successful color tuning of the Ag nanowire film, without suppressing the conductive and optical properties, is demonstrated by loading anionic blue dye onto PEI-mPEG-modified Ag nanowires.
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Room-temperature densification of MgO bulk ceramics with dispersed nitride phosphor particles
Takahashi Emi, Takahashi Takuma, Tatami Junichi
CERAMICS INTERNATIONAL 47 ( 4 ) 5013 - 5018 2021.2 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Wave conversion materials with high thermal conductivity are necessary for high-power semiconductor lighting. Ceramics have higher thermal conductivity than existing matrices such as resin or glass in which phosphor particles are dispersed. However, the high densification of ceramics generally requires high-temperature sintering, which degrades and alters the phosphor particles. In this study, we aimed to achieve the high densification of MgO ceramics at room temperature. Applying high hydrostatic pressure with water addition improved the sample packing ratio and promoted the formation of Mg(OH)2. As a result, the relative density was ≥95%. Additionally, various nitride phosphor particles (CaAlSiN3:Eu2+, β-SiAlON:Eu2+, and α-SiAlON:Eu2+) were dispersed in the MgO matrix at room temperature without degrading the luminescence property. The thermal conductivity of the obtained sample was about 8 W m−1K−1, 40 times higher than that of the epoxy matrix.
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Iijima Motoyuki, Hasegawa Kenta, Tatami Junichi
ADVANCED POWDER TECHNOLOGY 32 ( 2 ) 472 - 479 2021.2 [Reviewed]
DOI Web of Science CiNii Research
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract A novel gel casting system using nonaqueous, multicomponent, and concentrated slurries was designed for manufacturing Si3N4 dense ceramics with complex structures. The proposed process involves the dispersion of reagent particles in α-terpineol aided by the saturated adsorption of polyethyleneimine partially complexed with oleic acid (PEI-OA) as well as the addition of small amounts of multifunctional acrylates (MAs). The occurrence of the Michael additive reaction between the MAs and the remaining amines of PEI-OA fixed on the reagent particles resulted in a gradual increase in the viscosity of the slurry until its solidification. Using the Si3N4/α-terpineol slurry as a model system, the effects of processing parameters such as OA complex ratio, particle volume fraction, and MA structures on the solidification behaviors were systematically investigated. A slurry having higher particle concentration which was treated with PEI-OA comprised from lesser OA ratio found to effectively solidify within 2 h when mixed with MA having larger number of acryloyl group per molecule. The proposed gel casting process was then applied to the multicomponent Si3N4–Y2O3–Al2O3–TiO2–AlN/α-terpineol system. The gel casted complex structured green compacts were successfully densified up to 98% by liquid phase sintering at 1750 °C under 0.9 MPa N2 gas pressure.
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Morita Seitaro, Iijima Motoyuki, Chen Yuanyi, Furukawa Taichi, Tatami Junichi, Maruo Shoji
ADVANCED POWDER TECHNOLOGY 32 ( 1 ) 72 - 79 2021.1 [Reviewed]
DOI Web of Science CiNii Research
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract In this paper, we demonstrated optical fiber-based stereolithography of alumina ceramics using concentrated slurry with low monomer content for enabling rapid firing of the printed green objects. Photo-cross-linkable alumina slurries were designed using a partial complex of polyethyleneimine and oleic acid (PEI-OA) as reactive polymer dispersants and multifunctional acrylates (MA) as monomers. The effects of the processing parameters, such as oleic acid contents, MA contents, particle contents, and particle sizes, on photocuring properties were systematically investigated. We found that the reactive amine sites of PEI-OA attached to particles and MA volume concentrations in the liquid phase were the most dominant factors to improve the photocuring properties. Therefore, a slurry composed of larger alumina particles with higher solid contents and PEI-OA with lower OA contents was more favorable for achieving photocuring under reduced MA content. The designed photocurable slurry was then applied to ceramic stereolithography using optical fiber. 3D alumina green parts were drawn by passing blue laser beam through an optical fiber in a droplet of photocuring slurry and dense sintered alumina were successfully fabricated by rapid drying (
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マイクロカンチレバー曲げ試験によるセラミックスのメソ領域力学特性評価
多々見 純一
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 56 ( 1 ) 3 - 6 2021.1
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Single Work
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多機能性修飾剤による濃厚系スラリーの分散制御とセラミックスプロセッシング
飯島 志行, 多々見 純一
Journal of the Society of Inorganic Materials, Japan : セッコウ・石灰・セメント・地球環境の科学 / 無機マテリアル学会 編 28 ( 410 ) 40 - 44 2021.1
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：無機マテリアル学会 Joint Work
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波長掃引型光コヒーレンストモグラフィーによるセラミックス内部構造の非破壊評価技術
高橋 拓実, 多々見 純一
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 56 ( 1 ) 7 - 10 2021.1
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Joint Work
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Junichi Tatami, Yumi Imoto, Tsukaho Yahagi, Takuma Takahashi, Motoyuki Iijima
Journal of the European Ceramic Society 40 ( 7 ) 2634 - 2641 2020.7
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract The relationship between the bending strength of bulk porous SiC ceramics and the grain boundary strength measured using microcantilever beam specimens of SiC bicrystals was investigated. The average value of the grain boundary strength was 39.2 GPa, and its higher value was roughly equal to that derived using an ab-initio calculation. The strengths of the specimens having only one neck were estimated by analyzing the effect of the specimen size on the strength of bulk porous SiC ceramics and by also analyzing the grain boundary strength and the stress concentration at the neck surface. The estimated strengths were generally consistent of the order of several hundred MPa, meaning that the strength of porous SiC ceramics should be dependent on the stress concentration at the neck and the grain boundary strength. Furthermore, they were in a better agreement using smaller neck curvature, smaller neck diameter, and lower grain boundary strength.
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Yamaguchi, H; Tatami, J; Yahagi, T; Nakano, H; Iijima, M; Takahashi, T; Kondo, T
JOURNAL OF MATERIALS SCIENCE 55 ( 17 ) 7359 - 7372 2020.6 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Arita Ryoya, Iijima Motoyuki, Fujishiro Yoko, Morita Seitaro, Furukawa Taichi, Tatami Junichi, Maru … Show more authors
Arita Ryoya, Iijima Motoyuki, Fujishiro Yoko, Morita Seitaro, Furukawa Taichi, Tatami Junichi, Maruo Shoji Hide authors
COMMUNICATIONS MATERIALS 1 ( 1 ) 1 2020.5 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC Joint Work
<jats:title>Abstract</jats:title><jats:p>Photo-curable suspensions are important materials for shaping complex-structured ceramic and glass components. However, most systems undergo slow debinding and sintering so to avoid structural collapse by rapid gas generation from polymers. Here, we propose a new strategy to fabricate interparticle photo-cross-linkable suspensions for rapid three-dimensional structuring with short debinding and sintering times. SiO<jats:sub>2</jats:sub> particles modified with polyethyleneimine complexed with oleic acid (PEI-OA) are dispersed into a refractive-index-tuned solvent, where a photo-radical initiator and a lower-than-typical amount of multifunctional acrylates (MAs) were dissolved. The SiO<jats:sub>2</jats:sub> suspension is cured by the photo-radical polymerization of MA and the Michael additive reaction between polymerized MA and amino groups of PEI-OA on SiO<jats:sub>2</jats:sub> particles. These photo-curable suspensions can be employed in various shaping processes, from micro-scale stereolithography to centimeter-scale silicone molding. The SiO<jats:sub>2</jats:sub> green compacts with complex structures are also debinded and sintered into transparent glass components by rapid heating.</jats:p>
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Hiroshi Yamaguchi, Junichi Tatami, Tsukaho Yahagi, Hiromi Nakano, Motoyuki Iijima, Takuma Takahashi … Show more authors
Hiroshi Yamaguchi, Junichi Tatami, Tsukaho Yahagi, Hiromi Nakano, Motoyuki Iijima, Takuma Takahashi, Toshiyuki Kondo Hide authors
Journal of Materials Science 55 ( 17 ) 7359 - 7372 2020.3
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC Joint Work
Silicon is widely used within energy, electro-mechanical, environmental devices by nanostructural control. As silicon parts constitute structural components whose size is ever decreasing, it is critical to understand the mechanical properties of single crystal silicon from precise measurements of load and displacement using microscopic sample in sub-micron and macroscopic scales. Here, the mechanical properties of single crystal silicon were precisely evaluated by bending tests at room temperature using microcantilever beam specimens having a several micron size. The microcantilever beam specimens were prepared using a focused ion beam technique, followed by loading the tip of the specimens. The smaller specimens deformed nonlinearly and then fractured. The unloaded specimen after nonlinear deformation showed permanent strain and many dislocations close to the region where high tensile stress was applied. This means that the nonlinear stress–strain relationship in the very high bending stress is determined by plastic deformation controlled by dislocation despite occurring at room temperature. The bending strength increased with a decrease in specimen size, and the smallest specimens had close to ideal strength. The size of the region where the dislocations accumulated in high density corresponded to the flaw size estimated from the fracture mechanics. This means that the bending strength of the microcantilever beam specimens of silicon is dominated by newly generated defects resulting from dislocations; in other words, the size effect of bending strength of silicon at the micrometer scale is controlled by the accumulation of newly formed dislocations because the dense dislocation region should be lower in a smaller-sized specimen.
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Morita Seitaro, Iijima Motoyuki, Tatami Junichi
ADVANCED POWDER TECHNOLOGY 31 ( 2 ) 746 - 754 2020.2 [Reviewed] [Invited]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Although many colloidal assembling systems have been reported, most systems suffer from severe aggregation under high solid concentrations, which can often be observed in typical hetero-aggregation system. In this study, we created a hetero-assembly system using concentrated (~50 vol%) suspensions by mixing large SiO2 particles modified with polyacrylic acid partially complexed with oleylamine (PAA-OAm) and small SiO2 particles modified with polyethyleneimine partially complexed with oleic acid (PEI-OA) in a non-aqueous solvent. We demonstrated that hetero-assembly is driven by the interactions between the uncomplexed carboxyl/amine groups of the PAA/PEI present on the particles, while severe aggregation is simultaneously prevented by the steric repulsions of the aliphatic oleyl chains. Comparison of the cross sections of the in-situ solidified hetero-assembled suspensions with those of ideally assembled structures which were reproduced by a simulation considering the statistical distribution of particles strongly supported successful particle assembling via the proposed approach. The results revealed that the OA content in the PEI-OA complex was the dominant factor that controlled the dispersion and assembling state of the binary particles. The significance of this study is that our findings will provide a class of colloidal dispersion state which binary particles were assembled in a high solid content suspension without forming strong aggregates.
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光コヒーレンストモグラフィーによるAl₂O₃焼結体の内部構造観察
高橋 拓実, 多々見 純一
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 55 ( 2 ) 103 - 107 2020.2
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Joint Work
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Iijima Motoyuki, Morita Seitaro, Tatami Junichi
Journal of the Society of Powder Technology, Japan 57 ( 1 ) 19 - 24 2020.1 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Society of Powder Technology, Japan Single Work
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Preparation of Nitride Phosphor Particle Dispersed h-BN/Glass Composites
Torase Natsumi, Tatami Junichi, Iijima Motoyuki, Takahashi Takuma
Journal of the Society of Powder Technology, Japan 57 ( 3 ) 137 - 143 2020 [Reviewed]
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Society of Powder Technology, Japan Joint Work
<p>Wavelength conversion materials with high thermal conductivity and heat resistance have been strongly desired for high power semiconductor lighting source. Glass has higher heat resistances at elevated temperatures than resin and dispersion of high thermal conductive particles should result in the improvement of thermal conductivity of the composites. In this study, the composites of phosphate glass dispersing nitride phosphor and high thermal conductive particles were fabricated instead of typical composites of resins and oxide phosphors. As a result of verification of reactivity of the nitride phosphor and the high thermal conductive particles with the phosphate glass, between the glass and fillers, the firing temperature was set to 500°C and h-BN particles were selected as high thermal conductive particles. Dense nitride phosphor particles dispersed h-BN/glass composites were successfully obtained by hot-pressing. Thermal conductivity normal to hot-pressing direction was higher than that parallel to hot-pressing direction, and it increased with an increase in the hot-pressing pressure and the quantity of dispersed h-BN particles because of higher density and better orientation of the h-BN particles. Consequently, the nitride phosphor particle dispersed h-BN/glass composites with the thermal conductivity of 9.4 W/(m<sup>−1</sup>·K<sup>−1</sup>) were obtained.</p>
Other Link： https://ci.nii.ac.jp/naid/130007844899
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OKAZAKI Hiroya, KOBAYASHI Ryota, HASHIMOTO Rei, FUKUSHI Emiko, TATAMI Junichi
Journal of the Ceramic Society of Japan 128 ( 11 ) 991 - 994 2020 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Last author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
<p>We successfully fabricated dense aluminum nitride (AlN) ceramics containing AlN whiskers by low-temperature pressureless sintering and evaluated their microstructures, thermal conductivities, and mechanical strengths. Furthermore, the anisotropy of thermal conductivities caused by the orientation of AlN whiskers was also evaluated. The thermal conductivities of the samples measured in parallel and perpendicular to the longer direction of AlN whiskers were 98 and 67 W m<sup>−1</sup> K<sup>−1</sup>, respectively. The bending strengths of the samples without and with AlN whiskers were 147 and 235 MPa, respectively. From the observation of the fracture surface of the samples, AlN whiskers in the samples probably withstand the fracture originating from weak grain boundaries.</p>
Other Link： https://ci.nii.ac.jp/naid/130007934280
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TAKAHASHI Takuma, TATAMI Junichi
Journal of the Japan Society of Powder and Powder Metallurgy 67 ( 11 ) 615 - 620 2020 [Reviewed]
Authorship：Last author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Powder and Powder Metallurgy Joint Work
<p>Uniaxial pressing is a utilized technique to prepare powder compacts in regions of ceramics, metal, drug, and functional food. On the other hand, it is known that the inhomogeneous structures are induced by stress distribution resulting from applying the anisotropic stress field to the powder bed and they become the origin which forms defect degrading the performance of products. However, the generation process of inhomogeneous structures has not been clarified experimentally. Directly understanding the formation mechanism of the internal structure during uniaxial pressing is very important to control the particle-assembled structure in the powder bed and the quality of products. In this work, the change process in void morphology under uniaxial pressing was observed dynamic-two-dimensionally and intermittent-three-dimensionally by the novel observation system composed of swept-source optical coherence tomography (SS-OCT) and material testing machine. Moreover, the detected voids were evaluated quantitively to directly clarify particle-packing behavior on the initial stage of pressing.</p>
Other Link： https://ci.nii.ac.jp/naid/130007939842
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Carrier Depletion near the Grain Boundary of a SiC Bicrystal
Kim Young-Wook, Tochigi Eita, Tatami Junichi, Kim Yong-Hyeon, Jang Seung Hoon, Javvaji Srivani, Jun … Show more authors
Kim Young-Wook, Tochigi Eita, Tatami Junichi, Kim Yong-Hyeon, Jang Seung Hoon, Javvaji Srivani, Jung Jeil, Kim Kwang Joo, Ikuhara Yuichi Hide authors
SCIENTIFIC REPORTS 9 ( 1 ) 18014 2019.11 [Reviewed]
DOI Web of Science Scopus PubMed CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC Joint Work
<jats:title>Abstract</jats:title><jats:p>Silicon carbide (SiC) bicrystals were prepared by diffusion bonding, and their grain boundary was observed using scanning transmission electron microscopy. The n-type electrical conductivity of a SiC single crystal was confirmed by scanning nonlinear dielectric microscopy (SNDM). Dopant profiling of the sample by SNDM showed that the interface acted as an electrical insulator with a ~2-μm-thick carrier depletion layer. The carrier depletion layer contained a higher number of oxygen impurities than the bulk crystals due to the incorporation of oxygen from the native oxide film during diffusion bonding. Density functional theory calculations of the density of states as a function of the bandgap also supported these findings. The existence of a carrier depletion layer was also confirmed in a p-type polycrystalline SiC ceramic. These results suggest that the electrical conductivity of SiC ceramics was mostly affected by carrier depletion near the grain boundary rather than the grain boundary itself.</jats:p>
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Iijima Motoyuki, Tsutsumi Takaya, Saito Marina, Tatami Junichi, Moriya Toshimitsu, Kumada Tatsuya, … Show more authors
Iijima Motoyuki, Tsutsumi Takaya, Saito Marina, Tatami Junichi, Moriya Toshimitsu, Kumada Tatsuya, Izawa Hiroyuki Hide authors
ADVANCED POWDER TECHNOLOGY 30 ( 9 ) 1782 - 1788 2019.9 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Epoxy resin-grafted SiO2 nanoparticles stabilized in toluene were successfully designed by the simultaneous surface modification of SiO2 nanoparticles during bead milling which involves the adsorption of polyethyleneimine-oleic acid complex (PEI-OA) and epoxy resin grafting to the free amine groups of PEI-OA (PEI-OA-Epoxy). The effectiveness of epoxy grafting on the properties of the SiO2/epoxy based nanocomposites were investigated using a bead-milled SiO2/toluene suspension stabilized with PEI-OA, PEI-OA-Epoxy, and a complex of PEI and an anionic surfactant comprising an epoxy-soluble polyethylene glycol-based chain (PEI-AS). While SiO2 nanoparticles were pulverized with similar sizes (c.a. 126–171 nm) and stabilized in toluene with any of the three surface modifications, PEI-OA-stabilized SiO2 nanoparticles aggregated during processing epoxy-based composites. PEI-AS- and PEI-OA-Epoxy-stabilized SiO2 nanoparticles maintained their dispersion stability, however, the epoxy composites with PEI-OA-Epoxy-stabilized SiO2 nanoparticles exhibited better material properties, such as increase in the strain at fracture and higher Tg.
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Iijima Motoyuki, Hayakawa Masahiro, Tatami Junichi, Nakamura Koichiro, Nagashima Shinichi
CHEMICAL ENGINEERING SCIENCE 203 113 - 121 2019.8 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Nanoscale structured composite particles consisting of spherical porous SiO 2 particles with nanoscaled surface roughness as the core particles and SiO 2 nanoparticles as the depositing particles were designed using a high-shear mechanical composing process to develop a powder material that can form a layer with apparent rapid drying properties. The spherical porous SiO 2 core particles and depositing nanoparticles were selected to enhance the water extension on the core particle surface and amongst the composite particles in the powder layer, respectively. The effects of the composite particle nanoparticle content on the morphology of the composite particles and their relationships with the water droplet extending and drying properties in the powder layer of the designed composite particles were systematically investigated based on FE-SEM observations, characterization of N 2 adsorption/desorption isotherms, and 1 H spin-spin relaxation rate measurements of composite particles. The FE-SEM observations show that the pulverized nanoparticles could be successfully attached to porous core particles without the core particles collapsing. The reduction of the specific surface area and increase of the particle specific external surface area after the compositing process strongly supported the fact of nanoparticle attachment. While a small amount of nanoparticle attachment decreased the water droplet extended area, wet area circularity, and apparent drying rate, 15 wt% loading of the pulverized nanoparticles resulted in a drastic increase of the water extended area, wet area circularity, and apparent drying rate.
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Sakamoto Fumika, Takahashi Takuma, Tatami Junichi, Iijima Motoyuki
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 127 ( 7 ) 462 - 468 2019.7 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
<p>Non-destructive analysis is important in terms of improving the reliability of ceramics. In the study, the internal structure of Al<sub>2</sub>O<sub>3</sub> ceramics with artificial pores was observed via optical coherence tomography (OCT). The OCT observation was performed on a surface perpendicular to the tensile surface of the specimen. The spherical pores were successfully observed via OCT. The strength and fracture origin were predicted from the size and position of the observed pores. The lowest predicted strength (which is realized as the strength of the specimen) was in agreement with the bending strength obtained via three-point bending tests. The actual fracture origin observed by scanning electron microscope was also the same as that predicted via the OCT observation. Thus, the results indicated that the nondestructive testing via OCT was useful in terms of predicting the strength and fracture origin of ceramics.</p>
Other Link： https://ci.nii.ac.jp/naid/130007672941
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Journal of the Ceramic Society of Japan 127 ( 6 ) 335 - 338 2019.6 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130007658173
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Anisotropic sintering shrinkage and microstructural evolution of c-axis-oriented Si3N4 ceramics
Takahashi Takuma, Tatami Junichi, Nakano Hiromi, Tanaka Satoshi
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 127 ( 6 ) 435 - 442 2019.6 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
<p>High-thermal-conductivity Si<sub>3</sub>N<sub>4</sub> ceramics are desired for substrates in SiC power devices. We successfully fabricated highly <i>c</i>-axis-oriented Si<sub>3</sub>N<sub>4</sub> ceramic by casting in a rotating-magnetic field and then sintered using a conventional gas pressure. As a result, the <i>c</i>-axis orientation of Si<sub>3</sub>N<sub>4</sub> grains effectively improves the thermal conductivity. The sintering behavior of <i>c</i>-axis-oriented Si<sub>3</sub>N<sub>4</sub> ceramics was investigated. The linear shrinkage ratio in the <i>c</i>-axis-oriented direction was smaller than that in the direction normal to the <i>c</i>-axis-oriented direction. Fine <i>c</i>-axis-oriented structures resulted from the orientation of β-Si<sub>3</sub>N<sub>4</sub> seeds during the casting because they played as templates controlling the grain growth of β-Si<sub>3</sub>N<sub>4</sub> nuclei and inducing the anisotropic sintering shrinkage.</p>
Other Link： https://ci.nii.ac.jp/naid/130007658163
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多々見 純一, 米屋 勝利
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 54 ( 6 ) 401 - 403 2019.6
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Joint Work
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KOBAYASHI Takuto, SUN Jinyi, FURUKAWA Taichi, TAKAHASHI Takuma, TATAMI Junichi, MARUO Shoji
The Proceedings of the Symposium on Micro-Nano Science and Technology 2019 ( 0 ) 20am2PN215 2019
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Society of Mechanical Engineers Joint Work
<p>In this study, a microstereolithography technique of carbon fiber (CF) reinforced microsructures using magnetic field orientation has been developed. In this method, a CF composite photopolyemr is previously prepared on a PDMS well and the containing CFs are orientated with low magnetic field. Then, a 3D model is fabricated by the laboratoty-made stereolithography system based on pulling-up method. In experiments, the viscosity of the composite material was investigated to keep the orientation of CF on the PDMS well after pulling up of solidified polymer layers. CFs included in the high viscous photopolymer could be oriented by local heating even when a low magnetic field was applied. Finally, a 3D model constructed with multiple layers, in which CF.</p>
Other Link： https://ci.nii.ac.jp/naid/130007846870
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Morita Seitaro, Iijima Motoyuki, Tatami Junichi
ADVANCED POWDER TECHNOLOGY 29 ( 12 ) 3199 - 3209 2018.12 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract A Si-based slurry containing Si particles covered with Y2O3 and MgO nanoparticles (NPs) has been successfully prepared and then applied to shape Si-based green compacts for the fabrication of silicon nitride (Si3N4) ceramics via post-reaction sintering. It was found that Y2O3 and MgO NPs modified with polyethyleneimine-oleic acid complex (PEI-OA) could be effectively attached to Si particles by simple mixing in dense toluene slurry. Field emission scanning electron microscopy observations confirmed the attachment of PEI-OA-modified sintering aids to Si particles without forming large NP agglomerates. The adsorption of the PEI-OA-modified sintering aids and PEI-OA on the surface of Si particles drastically improved the stability of the Si-based toluene slurry, which was subsequently molded through wet vacuum casting and dewaxed to fabricate a Si-based green body. The obtained green body was nitrided at 1375 °C for 4 h at a N2 pressure of 0.15 MPa and further sintered at 1850 °C for 2 h at a N2 pressure of 0.9 MPa. The adsorption of sintering aid particles on the Si surface reduced the number of contact points between Si particles in the green body, which effectively suppressed the Si melting process during nitriding and improved the characteristics of the produced nitride body such as the degree of nitriding and α/(α+β) ratio of Si3N4, leading to the successful fabrication of high-density Si3N4 ceramics during the subsequent densification step.
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Iijima Motoyuki, Okamura Naoki, Tatami Junichi
ADVANCED POWDER TECHNOLOGY 29 ( 12 ) 3440 - 3447 2018.12 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract The effect of fatty acid structure of polyethyleneimine (PEI)-fatty acid complex, which was designed as a polymer dispersant for multi-component non-aqueous slurries, on the overall processing chain of Si3N4 ceramics involving slurry stabilization, spray drying, compaction, and liquid sintering was investigated using PEI-oleic acid (PEI-OA) and PEI-isostearic (PEI-ISA) complexes. Si3N4-Y2O3-Al2O3-AlN-TiO2/toluene slurries were selected as a real model for Si3N4-based multicomponent slurries. It was observed that both PEI-OA and PEI-ISA can stabilize Si3N4-Y2O3-Al2O3-AlN-TiO2/toluene slurries; however, the PEI-ISA system tended to have slightly higher slurry viscosity, which was suspected to be due to the interactions between protruded PEI segments among short ISA chains. The spray-dried granules from PEI-ISA-stabilized slurry were observed to have filled structures with higher surface roughness whereas those prepared from PEI-OA-stabilized slurry were observed to have hollow-structured granules. The granules prepared from PEI-OA slurry had improved flow and compaction properties with higher relative density of green compacts compared with those prepared from PEI-ISA-stabilized slurry, whereas the relative density and microstructural homogeneity of S3N4 ceramics sintered at 1600 °C for 2 h were observed to be higher for the PEI-ISA system. It is suspected that PEI-OA effectively improved the dispersion stability of multicomponent slurries and flow/compaction properties of granules; however, the inhomogeneous microstructures of green compacts induced by the hollow-structured granules had an adverse effect on the sintering of Si3N4 ceramics.
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S4 ゼオライトの新規調製法 ～高速合成法～
脇原 徹
粘土科学討論会講演要旨集 62 ( 0 ) 20 - 21 2018.9
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (research society, symposium materials, etc.) Publisher：一般社団法人日本粘土学会 Single Work
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Iijima Motoyuki, Tsutsumi Takaya, Kataoka Momoko, Tatami Junichi
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS 545 110 - 116 2018.5 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract An anionic surfactant (AS) comprising a phosphate ester head group and a functional organic chain branched into a hydrophilic polyethylene glycol-based chain and a hydrophobic alkyl-based chain was complexed with polyethyleneimine (PEI) and applied as universal surface modifier for the fabrication of nanoparticles dispersible in various solvents. The complex formation could be achieved by simply mixing PEI with the AS in solvents such as toluene. While PEI was insoluble in toluene due to its hydrophilic nature, addition of the AS assisted its dissolution due to complex formation between the amine group of PEI and the phosphate group of the AS. The designed PEI-AS complex effectively adsorbed on numerous particles including metal oxides (Al2O3, Y2O3, and SiO2), metal nitrides (AlN), and metal species (Si and Ni), and was applicable to various surface modification processes. For simultaneous bead milling pulverization and surface modification of gas-phase synthesized SiO2 nanoparticles with 2.6 mg/m2 of PEI-AS, the number-based size distribution of the SiO2 nanoparticles reduced to several tens of nanometers after milling, and the resultant pulverized/surface-modified nanoparticles were dispersible in a wide range of organic solvents such as methanol, MEK, IPA, THF, MMA, EtOAc, and toluene. The ligand-exchange process of oleylamine-capped Ag nanoparticles in toluene with 2.0 mg/m2 of PEI-AS was also effective in dispersing Ag nanoparticles in various organic solvents without forming severe aggregation.
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Observation of Internal Structure of Ceramics and Slurry by Optical Coherence Tomography
TAKAHASHI Takuma, TATAMI Junichi, SAKAMOTO Fumika, ITO Hidetaka, IIJIMA Motoyuki
Journal of the Japan Society of Powder and Powder Metallurgy 65 ( 10 ) 659 - 663 2018 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Powder and Powder Metallurgy Joint Work
<p>Optical coherence tomography (OCT) is an observation technique utilizing optical interferometry. Images of the internal structure of opaque materials can be obtained dynamically and three-dimensionally in a few seconds. In this work, the internal structures of ceramic sintered body and slurry was observed by OCT. In the case of Al<sub>2</sub>O<sub>3</sub> ceramics, an artificially induced spherical defect having smaller than 50 µm in diameter which lies 700 μm below the top surface was observed successfully. Furthermore, it was observed that the internal structure of Al<sub>2</sub>O<sub>3</sub> slurry was drastically changed during drying, followed by formation of a crack in the dried green body.</p>
Other Link： https://ci.nii.ac.jp/naid/130007507018
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セラミックスプロセスチェーンの最適化のための光コヒーレンストモグラフィー観察
高橋 拓実, 多々見 純一, 飯島 志行, 伊東 秀高, 田口 勇
Fine ceramics report 36 ( 2 ) 62 - 67 2018
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本ファインセラミックス協会 Joint Work
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Fujita Saho, Tatami Junichi, Yahagi Tsukaho, Takahashi Takuma, Iijima Motoyuki
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 37 ( 14 ) 4351 - 4356 2017.11 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Although Si3N4 ceramics are often utilized as structural components in the Al casting industry due to their excellent properties, they occasionally suffer breakage after long-term use. In this study, the bending strength, fracture toughness, and Young’s modulus in the vicinity of the Si3N4 ceramic surfaces after contact with molten Al were evaluated using microcantilever beam specimens, which were fabricated using a focused ion beam technique. Fracture testing of the specimens was carried out by nanoindentation. The bending strength of the ceramic surface before and after contact with molten Al was 5.89 ± 1.33 and 3.03 ± 0.28 GPa, respectively. The fracture toughness of the corroded layer in Si3N4 ceramics also decreased compared to that of the polished surface. Using fractography by observation with scanning electron microscopy, it was shown that changes in the grain boundary glassy phase resulted in the degradation of strength and fracture toughness.
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Fabrication of Ta-Nb-Al2O3 seal composites by laser radiation
Honma Takuya, Tatami Junichi
MATERIALS CHEMISTRY AND PHYSICS 200 402 - 406 2017.10 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Ceramic-metal (Al2O3-Nb) sealing was performed by melting an Al2O3 capillary using neodymium-doped yttrium aluminum garnet (Nd:YAG) laser irradiation. However, voids existed in the melting region. Since voids are the most important factor affecting the mechanical strength of seals, attempts were made to remove them by introducing annealing as an additional cooling step after the melting step during the sealing process with Nd:YAG laser irradiation. Simultaneously, a Ta mesh foil was used, wrapped around the surface of the Al2O3 capillary as a grain-growth inhibitor. In addition, another important factor affecting the mechanical strength of the sealing is control of the seal length. In this study, the influence of various Ta mesh foil form factors (hole area, space between holes, and Ta area) on the seal length in the melted A2O3 capillary for Al2O3-Nb seals was therefore investigated in order to elucidate the optimal factors to increase the seal length. It was found that both the Ta area and space between holes should be decreased to increase seal length. Moreover, as the ratio of the Ta area to the space between holes increased, the seal length increased as well.
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高出力LED照明向け透明蛍光SiAlON系バルクセラミックスの開発
高橋 拓実, 多々見 純一, 横内 正洋
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 52 ( 4 ) 245 - 248 2017.4
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Joint Work
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Morita Seitaro, Iijima Motoyuki, Tatami Junichi
ADVANCED POWDER TECHNOLOGY 28 ( 1 ) 30 - 36 2017.1 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract SiO2 nanoparticles (NPs) surface modified with polyethyleneimine-oleic acid complex (PEI-OA) has successfully prepared in a simple manner as a stabilizer of metal (Ni) fine particles (FPs) as well as a component of Ni/SiO2 composite particles. Starting from SiO2 NPs which were collected through centrifugation of commercial SiO2 colloids, it was found that PEI-OA can effectively adsorbed on collected SiO2 NPs surface during their redispersion process in toluene with the assistance of ultrasonication. The aggregated particle size (Z-average size) in toluene could be successfully reduced to c.a. 100 nm under saturated adsorption of PEI-OA. It was also found that PEI-OA-modified SiO2 NPs can effectively attach to the Ni FPs by a simple mixing process in toluene. The FE-SEM observation confirmed the adsorption of the PEI-OA-modified SiO2 NPs on the Ni FPs without forming severe NP aggregates. Owing to the attachment of the PEI-OA-modified SiO2 NPs with surfaces that are compatible to toluene and α-terpineol, the suspension stability of the Ni/SiO2 composite particles in these solvents drastically improved. The result was confirmed by the effective reduction of the sedimentation velocity of diluted suspensions as well as by the reduction of the viscosity of dense suspensions.
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Spark plasma sintering of silicon nitride using nanocomposite particles
Jeong Kwangjin, Tatami Junichi, Iijima Motoyuki, Nishimura Toshiyuki
ADVANCED POWDER TECHNOLOGY 28 ( 1 ) 37 - 42 2017.1 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract The spark plasma sintering (SPS) of silicon nitride (Si 3 N 4 ) was investigated using nanocomposite particles composed of submicron-size α-Si 3 N 4 and nano-size sintering aids of 5 wt% Y 2 O 3 and 2 wt% MgO prepared through a mechanical treatment. As a result of the SPS, Si 3 N 4 ceramics with a higher density were obtained using the nanocomposite particles compared with a powder mixture prepared using conventional wet ball-milling. The shrinkage curve of the powder compact prepared using the mechanical treatment was also different from that prepared using the ball-milling, because the formation of the secondary phase identified by the X-ray diffraction (XRD) method and liquid phase was influenced by the presence of the sintering aids in the powder compact. Scanning electron microscopy (SEM) observations showed that elongated grain structure in the Si 3 N 4 ceramics with the nanocomposite particles was more developed than that using the powder mixture and ball-milling because of the enhancement of the densification and α-β phase transformation. The fracture toughness was improved by the development of the microstructure using the nanocomposite particles as the raw material. Consequently, it was shown that the powder design of the Si 3 N 4 and sintering aids is important to fabricate denser Si 3 N 4 ceramics with better mechanical properties using SPS.
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Synthesis of Zeolite from Waste Perlite by Hydrothermal Treatment
KASAI Makoto, KOBAYASHI Yosei, TOGO Masakazu, KAMITANI Masataka, KONDO Mitsunori, WAKIHARA Toru, NA … Show more authors
KASAI Makoto, KOBAYASHI Yosei, TOGO Masakazu, KAMITANI Masataka, KONDO Mitsunori, WAKIHARA Toru, NAKAHIRA Atsushi Hide authors
Journal of MMIJ 133 ( 8 ) 182 - 187 2017
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Mining and Materials Processing Institute of Japan Joint Work
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Jeong Kwangjin, Tatami Junichi, Iijima Motoyuki, Takahashi Takuma
JOURNAL OF ASIAN CERAMIC SOCIETIES 4 ( 3 ) 351 - 356 2016.9 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Informa UK Limited Joint Work
AbstractNanoparticles are being extensively investigated in industries and academia due to their widespread applications in various areas of science and manufacturing. Unfortunately, nanoparticles easily aggregate. This problem of nanoparticle aggregation creates challenges for various applications. In this study, we focus on using nanocomposite particles prepared via mechanical treatment to pulverize the aggregated Y2O3 nanoparticles. CaCl2 and aggregated Y2O3 nanoparticles were mechanically treated using a process in which high shear and compressive stress are applied to them in order to generate nanocomposite particles. In order to rinse out CaCl2, the nanocomposite particles were then added to distilled water to dissolve the CaCl2 cores, and they were centrifuged before supernatant solution was decanted. The recovered Y2O3 nanoparticles had a significantly smaller particle size and larger specific surface area than the aggregates. Thus, we confirmed that the aggregated Y2O3 nanoparticles were effectively pulverized in a short time by using nanocomposites prepared by mechanical treatment. Further, the relative density of the sintered body prepared from the pulverized Y2O3 nanoparticles was higher than that of the as-received and ball-milled Y2O3 nanoparticles.
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Iijima Motoyuki, Kawaharada Yasuhiro, Tatami Junichi
JOURNAL OF ASIAN CERAMIC SOCIETIES 4 ( 3 ) 277 - 281 2016.9 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Informa UK Limited Joint Work
AbstractA series of polyethyleneimine (PEI)–fatty acid complexes using oleic acid (OA), isostearic acid (ISA), and stearic acid (SA) were prepared through a simple process. While PEI was not soluble in toluene, the complex with OA and ISA became soluble when its additive content was greater than 5mol% based on the ethyleneimine (EI) unit of PEI. PEI–SA had similar solubility in toluene when more than 5mol% of SA was added; however, the complex precipitated when the additive ratio of SA was increased to 40mol%. The effect of fatty acid of PEI complexes on their TiO2 nanoparticle adsorption properties and the flow curves of TiO2 nanoparticle/toluene suspension was then studied using PEI complexed with 30mol% of fatty acids. Surprisingly, while PEI–OA and PEI–ISA complexes effectively adsorbed on TiO2 nanoparticles until saturation, the amount of adsorbed PEI–SA increased continuously. Comparing the flow curves of TiO2/toluene suspensions under 1.4mg/m2 addition of PEI–fatty acid complexes, where PEI–OA and PEI–ISA were under saturated adsorption, it was confirmed that PEI–OA effectively stabilizes TiO2 nanoparticles in toluene without imparting thixotropic properties up to 30vol%, while the suspensions with PEI–SA and PEI–ISA were solidified at lower volume contents and had high thixotropic properties.
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Takahashi Takuma, Sado Mariko, Sugimoto Nanako, Tatami Junichi, Iijima Motoyuki, Inagaki Satoshi, K … Show more authors
Takahashi Takuma, Sado Mariko, Sugimoto Nanako, Tatami Junichi, Iijima Motoyuki, Inagaki Satoshi, Kubota Yoshihiro, Yamamoto Isao, Tanaka Satoshi Hide authors
ADVANCED POWDER TECHNOLOGY 27 ( 5 ) 2005 - 2011 2016.9 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract c-axis oriented Si3N4 ceramics were fabricated by applying a low static magnetic field. Conventionally, c-axis oriented Si3N4 ceramics are fabricated using a rotating magnetic field of over 10 T considering the anisotropy and the magnitude of diamagnetic susceptibility between c- and a-axes. In this work, multilayered-graphene was used for orienting rod-like β-Si3N4 particles as graphene exhibits a high diamagnetic anisotropy. The multilayered-graphene was coated with their orientation on the surface of rod-like β-Si3N4 particles by using a mechanical treatment process. As a result, the c-axis of multilayered-graphene-coated β-Si3N4 particles were oriented parallel direction to the applied magnetic field even at 0.4 T. In addition, c-axis oriented Si3N4 ceramics were fabricated successfully by adding a small quantity of multilayered-graphene-coated β-Si3N4 particles as seeds. The thermal conductivity of the c-axis oriented Si3N4 ceramics prepared with a magnetic field of 0.4 T exhibited anisotropy with a higher value achieved in the c-axis oriented direction.
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Jeong Kwangjin, Tatami Junichi, Iijima Motoyuki, Takahashi Takuma
CERAMICS INTERNATIONAL 42 ( 10 ) 11554 - 11561 2016.8 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Post-reaction sintering of a powder compact of Si and sintering aids is a useful technique for fabricating silicon nitride (Si3N4) ceramics at low costs. In order to inhibit the inhomogeneous and uncontrollable exothermic nitridation of Si in the powder compact, Si–Y2O3–Al2O3 nanocomposite particles are designed as an aid for post-reaction sintering. These Si–Y2O3–Al2O3 nanocomposite particles are prepared via mechanical treatment applying high shear stress. Scanning electron microscopy (SEM) observations show that Y2O3 and Al2O3 particles are homogenously dispersed, and fixed to the Si particles. A green compact prepared using the Si–Y2O3–Al2O3 nanocomposite particles results in lower electrical resistivity than that prepared using a powder mixed by wet ball-milling, which suggests that Si particles in the green compact prepared using the nanocomposite particles are isolated by Y2O3 and Al2O3 particles. The isolation of Si particles by the sintering aids successfully prevents the Si particles from melting and agglomerating during the nitridation process, resulting in a higher nitridation ratio and higher α-Si3N4 phase content due to the inhibition of rapid heat transfer caused by the exothermic reaction. The nitridation ratio also increases with the applied power during mechanical treatment. As a result of firing the homogeneously nitrided powder compacts at high temperatures, Si3N4 ceramics with homogeneous microstructure and improved density are successfully fabricated in this manner.
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多々見 純一
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 51 ( 6 ) 352 - 354 2016.6
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Single Work
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高橋 拓実, 多々見 純一, 田中 諭
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 51 ( 6 ) 385 - 388 2016.6
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Joint Work
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高橋 拓実, 多々見 純一
Optronics : 光技術コーディネートジャーナル 35 ( 6 ) 75 - 79 2016.6
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：オプトロニクス社 Joint Work
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Densification of AlN ceramics by spark plasma sintering under 1550 degrees C
Kobayashi Ryota, Nakajima Yoshihiro, Mochizuki Kenji, Harata Koichi, Goto Takashi, Iwai Kentaro, Ta … Show more authors
Kobayashi Ryota, Nakajima Yoshihiro, Mochizuki Kenji, Harata Koichi, Goto Takashi, Iwai Kentaro, Tatami Junichi Hide authors
ADVANCED POWDER TECHNOLOGY 27 ( 3 ) 860 - 863 2016.5 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract We fabricated AlN ceramics at sintering temperatures with a minimum of 1450 °C using spark plasma sintering (SPS) with Y 2 O 3 –CaO–B or Y 2 O 3 –CaO–LaB 6 sintering additives. The relative densities of the AlN ceramics sintered at 1500 °C for 10 min with a uniaxial pressure of 50 MPa exceeded 98%, indicating sufficient densification. However, with decreasing the sintering temperature to 1450 °C, the relative densities were decreased to ∼90%. An increase in the uniaxial pressure to 100 MPa or the extension of sintering time to 30 min were found to promote the densification of AlN ceramics. The relative densities of the AlN ceramics sintered reached 99% even at a sintering temperature of 1450 °C. The samples had dense and fine textures with an average grain size of ∼1 μm. The thermal conductivities of the samples varied with relative density between 30 and 80 W m −1 K −1 .
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Naito Makio, Ewsuk Kevin, Tatami Junichi, Iijima Motoyuki
ADVANCED POWDER TECHNOLOGY 27 ( 3 ) 797 - 798 2016.5 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Achievement of Ultrafast Synthesis of Zeolites
Wakihara Toru, Liu Zhendong, Takewaki Takahiko, Okubo Tatsuya
33 ( 1-2 ) 19 - 27 2016.4
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Association of Zeolite Joint Work
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Inhibition of grain growth by MgO in laser-melted Al2O3 capillary microstructure
Honma Takuya, Tatami Junichi
MATERIALS CHEMISTRY AND PHYSICS 171 1 - 5 2016.3 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract In this study, ceramic-metal (Al 2 O 3 –Nb) sealing was performed by melting an Al 2 O 3 capillary with Nd:YAG laser irradiation while using MgO as a grain-growth inhibitor. The effect of MgO on annealing during the cooling step was that it effectively prevented the formation of the extremely large voids that are typically formed in melted Al 2 O 3 capillaries by the decomposition of the sintered body. The solidification process is accompanied by the formation of grain boundaries, which causes the vapors generated by melting to diffuse along the grain boundary paths during annealing at the cooling step. However, the grains closer to the laser irradiation spot were larger than those further away, owing to variations in the distribution of MgO throughout the capillary structure. This phenomenon was due to the difference in the distribution of the temperature during the sealing process. Though grain growth was suppressed in the regions away from the laser irradiation spot, coarse grains were formed within the laser-irradiated region itself.
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LEE Hyun Min, TATAMI Junichi, KIM Do Kyung
124 ( 8 ) 800 - 807 2016 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
Microstructural evolution of Si<sub>3</sub>N<sub>4</sub> ceramics and thermal/mechanical properties were investigated with respect to the initial α-to-β ratios of the starting powders. The fast growth of elongated β-grains was observed in the α powder, while the growth of relatively equiaxed grains occurred in the β powder. In the cases where α/β mixed raw powder was used, exaggerated bimodal microstructural evolution occurred as a result of the abnormal grain growth. These microstructural variations of the Si<sub>3</sub>N<sub>4</sub> had a significant influence on the mechanical and thermal properties, such as strength, fracture toughness and thermal conductivity. The bimodal microstructure, which consisted of large elongated grains surrounded by fine matrix grains, resulted in both high flexural strength and high fracture toughness. Controlling the microstructural evolution, resulted in a high thermal conductivity of 86 W/mK, a high flexural strength of 912 MPa, and a high fracture toughness of 7.88 MPa.m<sup>1/2</sup> from α/β mixed raw powder. The achievement of both high thermal and mechanical properties of Si<sub>3</sub>N<sub>4</sub> ceramics was highly essential for thermal management applications.
Other Link： https://ci.nii.ac.jp/naid/130005255808
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TATAMI Junichi, HIRATSUKA Daisuke, OKADA Shigefumi, KOMEYA Katsutoshi, WAKIHARA Toru
124 ( 4 ) 375 - 380 2016 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
We propose a new master sintering curve (MSC) theory for liquid phase sintering in consideration of grain rearrangement and solution-precipitation in order to analyze the sintering behaviors of silicon nitride (Si<sub>3</sub>N<sub>4</sub>) powder compacts. We found that the MSC for liquid phase sintering is theoretically the same expression as that for solid-state sintering. Very fine high-purity powders of Si<sub>3</sub>N<sub>4</sub> Y<sub>2</sub>O<sub>3</sub>, Al<sub>2</sub>O<sub>3</sub>, AlN, and TiO<sub>2</sub> were used as the raw materials to make powder compacts. The degree of sintering shrinkages of the powder compacts, which contained different amounts of the sintering aids, were measured directly by the laser displacement measurement method using a dilatometer. Based on the displacements and the specimen dimensions, the shrinkage ratios and rates could be calculated. The sintering shrinkage behavior depended on the sintering aid used and the heating rate. The MSCs were obtained for shrinkage ratios of 0–2 and 2–15% corresponding to grain rearrangement and the solution-precipitation process, respectively. Finally, the apparent activation energies of sintering of Si<sub>3</sub>N<sub>4</sub> for grain rearrangement and the solution-precipitation process were found to be 251–294 and 345–430 kJ/mol, respectively, depending on the sintering aid used.
Other Link： https://ci.nii.ac.jp/naid/130005142410
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IIJIMA Motoyuki, TATAMI Junichi
Journal of Smart Processing 5 ( 6 ) 322 - 326 2016 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：Smart Processing Society for Materials, Environment & Energy (High Temperature Society of Japan) Joint Work
Other Link： https://ci.nii.ac.jp/naid/130007553990
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Spark Plasma Sintering of Functionally Graded SiO2/Mo Laminated Layer Material
Honma Takuya, Tatami Junichi
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY 13 ( 1 ) 50 - 55 2016 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>A functionally graded sintered body consisting of laminated SiO<jats:sub>2</jats:sub>/Mo layers was fabricated using spark plasma sintering. A high sintered‐body density was achieved using fine powders of SiO<jats:sub>2</jats:sub> (4.0 μm) and Mo (1.3 μm), which ensured no cracks were formed between layers. The highest joining stress (1.2 <jats:styled-content style="fixed-case">MP</jats:styled-content>a) was found to occur at the interface between SiO<jats:sub>2</jats:sub> layers with 0 and 8 vol% Mo, with the electrical resistance decreasing rapidly when the Mo content was increased to 13 and 22 vol%. This is attributed to the use of spark plasma sintering, suggesting further work is needed to fully optimize this process.</jats:p>
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Green Processing of Particle Dispersed Composite Materials
Tatami, J. and Nakano, H.
Green and Sustainable Manufacturing of Advanced Materials 245 - 265 2016
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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脇原 徹, 劉 振東, 武脇 隆彦, 大久保 達也
ゼオライト = Zeolite 33 ( 1・2 ) 19 - 27 2016
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ゼオライト学会 Joint Work
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Fabrication of Porous Alumina Ceramics Using Basic Aluminum Lactate as an Inorganic Binder
Tatami Junichi, Tsuchibuchi Gaku, Iijima Motoyuki
Journal of the Society of Powder Technology, Japan 53 ( 3 ) 132 - 135 2016 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Society of Powder Technology, Japan Joint Work
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Inagaki Satoshi, Hayashi Shunsuke, Yamada Narumi, Fukuoka Takuya, Matsumoto Masayuki, Wakihara Toru … Show more authors
Inagaki Satoshi, Hayashi Shunsuke, Yamada Narumi, Fukuoka Takuya, Matsumoto Masayuki, Wakihara Toru, Kubota Yoshihiro Hide authors
Journal of the Society of Powder Technology, Japan 53 ( 12 ) 810 - 819 2016
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Society of Powder Technology, Japan Joint Work
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Silicon Nitride Ceramics for Tribological Applications
Tatami, J. and Komeya, K.
Engineered Ceramics: Current Status and Future Prospects 124 - 141 2016 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Silicon Nitride Ceramics for Tribological Applications
Tatami, J. and Komeya, K.
Engineered Ceramics: Current Status and Future Prospects 124 - 141 2016 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Iijima Motoyuki, Okamura Naoki, Tatami Junichi
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 54 ( 51 ) 12847 - 12854 2015.12 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work
Polymeric dispersants that adsorb onto various types of fine particles have been designed through complex formation between cationic polyethyleneimine (PEI) and anionic oleic acid (OA) to improve particle surface compatibility with nonaqueous solvents. Complex formation involves the OA-assisted dissolution of PEI in a nonaqueous solvent (toluene) by ultrasonication. While PEI itself is immiscible in toluene, various molecular weights (MWs) of PEI (Mw = 600, 1800, and 10 000) visibly dissolved when, in the presence of more than 5-mol % PEI (based on the ethyleneimine (EI) unit of PEI), a complex formed between the carboxyl group of OA and the amines of PEI in toluene. Si3N4 and one of the typical multicomponent compositions for Si3N4 ceramic fabrication, Si3N4–Y2O3–MgO, were chosen to demonstrate the usage of PEI–OA complexes for improving nonaqueous slurry stability. While nontreated Si3N4 particles rapidly formed dense slurry aggregates followed by solidification in toluene, PEI associated with 30 mol % ...
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Distribution of Al2O3 crystal grains at interface of seal between Al2O3 and glass frit
Honma Takuya, Tatami Junichi
MATERIALS LETTERS 160 375 - 377 2015.12 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Polycrystalline aluminum oxide has been used to realize a higher luminance for the arc tubes of metal-halide lamps. However, cracks occasionally develop inside the glass frit used for sealing. The microstructures of samples, which were sealed by annealing during the cooling step of the sealing process, were investigated at the interface between the Al2O3 capillary and the glass frit. The Al2O3 grains remain semi-separated from the inner surface of the Al2O3 capillary. Consequently, Al2O3 crystal grains grew anisotropically in the radial direction of the seal by annealing during the cooling step of the sealing process. The number of crystals grains decreased continuously with the distance from the Al2O3 capillary, and a composition gradient was present with regard to the Al2O3 crystal grains. In other words, the sealing stress is also relaxed when the CTE gradually changes at the sealing interface. Therefore, the formation of cracks inside the glass frit in the axial direction of the Al2O3 capillary can be prevented by the growth of Al2O3 crystal grains.
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Mechanism of huge void generation in laser-melted Al2O3 Reply
Honma Takuya, Tatami Junichi
OPTICS AND LASER TECHNOLOGY 75 13 - 15 2015.12 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract The sealing of sintered ceramics with metal often results in the formation of huge voids that reduce the strength of the final structure. This study therefore investigates the mechanism of void formation during Nb-sealing of an Al2O3 capillary using Nd:YAG laser irradiation. It is found that during the initial stages of cooling the outer surface of the Al2O3 capillary solidifies rapidly, but the Nb wire used as the heat source remains at a higher temperature for longer. This causes any gases emitted from the sealing section at the time of melting to be constrained within the capillary, which eventually leads to the formation of huge voids.
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Yokoyama Takashi, Kato Keita, Meguro Takeshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Oka … Show more authors
Yokoyama Takashi, Kato Keita, Meguro Takeshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Okazaki Shinji, Ito Daisuke Hide authors
JOURNAL OF CERAMIC PROCESSING RESEARCH 16 ( 5 ) 531 - 535 2015.10 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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S. Inagaki, K. Sato, S. Hayashi, J. Tatami, Y. Kubota, T. Wakihara
ACS Appl. Mater. Interfaces 7 ( 8 ) 4488 - 4493 2015.8 [Reviewed]
DOI Web of Science Scopus PubMed CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work
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Tatami Junichi, Katayama Masaki, Ohnishi Masahiro, Yahagi Tsukaho, Takahashi Takuma, Horiuchi Takah … Show more authors
Tatami Junichi, Katayama Masaki, Ohnishi Masahiro, Yahagi Tsukaho, Takahashi Takuma, Horiuchi Takahiro, Yokouchi Masahiro, Yasuda Kouichi, Kim Do Kyung, Wakihara Toru, Komeya Katsutoshi Hide authors
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 98 ( 3 ) 965 - 971 2015.3 [Reviewed]
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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研究最先端 マイクロカンチレバー法によるソーダライムガラスの局所領域の破壊靭性評価
多々見 純一, 片山 正己, 飯島 志行
New glass 30 ( 1 ) 30 - 33 2015.3
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ニューガラスフォーラム Joint Work
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Luminescence Properties of New Blue-Emitting Sialon Polytypoid Phosphor
Fukuda Yumi, Tatami Junichi
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY 4 ( 7 ) R114 - R117 2015 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：The Electrochemical Society Joint Work
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多々見 純一
財団法人日本板硝子材料工学助成会成果報告書 Nippon Sheet Glass Foundation for Materials Science and Engineering report / 日本板硝子材料工学助成会 編 ( 36 ) 99 - 105 2015
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本板硝子材料工学助成会 Single Work
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高橋 拓実, 多々見 純一
Fine ceramics report 33 ( 1 ) 12 - 16 2015
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本ファインセラミックス協会 Joint Work
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光造形モールドを鋳型とした湿式成形によるセラミックスの微小構造形成
多々見 純一, 丸尾 昭二
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 49 ( 10 ) 875 - 879 2014.10
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Joint Work
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Honma Takuya, Tatami Junichi
JOURNAL OF MATERIALS SCIENCE 49 ( 17 ) 5878 - 5884 2014.9 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC Joint Work
SiO2–Mo composite compact bodies were fabricated by mixing SiO2 and Mo and then subjected to spark plasma sintering (SPS). In this study, the effects of the volume fraction of Mo and the SiO2/Mo particle-size ratio of the compact bodies on the relative bulk density and electrical conductivity of the obtained sintered bodies are discussed. The relative bulk density tended to decrease with increasing SiO2/Mo particle-size ratio and increasing Mo volume fraction, whereas the electrical conductivity increased with increasing SiO2/Mo particle-size ratio. These results suggest that the density of the regions containing SiO2 particles in the composite matrix significantly affects the degree of contact between the Mo particles (that form the conduction path). This in turn affects the SPS process, because SPS requires continuous conduction paths for the pulsed direct current to increase the temperature inside the materials. Therefore, when SPS is used to fabricate SiO2–Mo composite sintered bodies, it is important to select raw material powders that allow the SiO2/Mo particle-size ratio to be decreased or increased to obtain sintered bodies with high-relative bulk densities or high electrical conductivity, respectively.
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Honma Takuya, Sasaki Ikue, Tamura Nobuhiro, Tatami Junichi, Fujichika Shinichiro, Komeya Katsutoshi … Show more authors
Honma Takuya, Sasaki Ikue, Tamura Nobuhiro, Tatami Junichi, Fujichika Shinichiro, Komeya Katsutoshi, Meguro Takeshi Hide authors
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY 11 ( 2 ) 294 - 302 2014.3 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>In industrial high‐intensity discharge lamps, cracks and delaminations occasionally develop at the interface between <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub></jats:roman></jats:styled-content> and the <jats:styled-content style="fixed-case"><jats:roman>Mo</jats:roman></jats:styled-content> foil in the seal. Here, functionally graded <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub>‐Mo</jats:roman></jats:styled-content> materials for use in these lamps were fabricated by uniaxial compression casting and pressureless sintering. Consequently, vertical cracks developed across the sintered body layers, and interfacial cracks developed between the 100 wt% <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub></jats:roman></jats:styled-content> and 90 wt% <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub>‐Mo</jats:roman></jats:styled-content> layers. Therefore, the effects of residual stress, difference in the coefficient of thermal expansion (<jats:styled-content style="fixed-case">CTE</jats:styled-content>), and difference in the volume shrinkage on these cracks were investigated. Vertical cracks were suppressed when residual stress was relaxed by annealing near the annealing point of silica glass during the cooling step in the sintering process. Interfacial cracks were suppressed when the difference in the <jats:styled-content style="fixed-case">CTE</jats:styled-content> of the interface between the 100 wt% <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub></jats:roman></jats:styled-content> and 90 wt% <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub>‐Mo</jats:roman></jats:styled-content> layers was relaxed by inserting layers of 95 wt% <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub>‐Mo</jats:roman></jats:styled-content> between them. Furthermore, the suppression effect became stronger when the difference in the volume shrinkage of the layers was relaxed by sintering to join the separately sintered monolayers. Thus, the development of these cracks was influenced by the residual stress, <jats:styled-content style="fixed-case">CTE</jats:styled-content>, and volume shrinkage. Therefore, these cracks can be prevented by optimizing these factors.</jats:p>
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Torad, NL; Naito, M; Tatami, J; Endo, A; Leo, SY; Ishihara, S; Wu, KCW; Wakihara, T; Yamauchi, Y
CHEMISTRY-AN ASIAN JOURNAL 9 ( 3 ) 759 - 763 2014.3
DOI Web of Science PubMed CiNii Research
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:title>Abstract</jats:title><jats:p>Nanometer‐sized zeolite A with a large cesium (Cs) uptake capability is prepared through a simple post‐milling recrystallization method. This method is suitable for producing nanometer‐sized zeolite in large scale, as additional organic compounds are not needed to control zeolite nucleation and crystal growth. Herein, we perform a quartz crystal microbalance (QCM) study to evaluate the uptake ability of Cs ions by zeolite, to the best of our knowledge, for the first time. In comparison to micrometer‐sized zeolite A, nanometer‐sized zeolite A can rapidly accommodate a larger amount of Cs ions into the zeolite crystal structure, owing to its high external surface area. Nanometer‐sized zeolite is a promising candidate for the removal of radioactive Cs ions from polluted water. Our QCM study on Cs adsorption uptake behavior provides the information of adsorption kinetics (e.g., adsorption amounts and rates). This technique is applicable to other zeolites, which will be highly valuable for further consideration of radioactive Cs removal in the future.</jats:p>
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Matsuoka Mitsuaki, Tatami Junichi, Wakihara Toru
INNOVATIVE PROCESSING AND MANUFACTURING OF ADVANCED CERAMICS AND COMPOSITES II 243 117 - 120 2014 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Nanotechnology-based innovation for environmental, energy and biomedical applications
Sunilkumar, B. and Basu, B. and Tatami, J. and Suzuki, A.
Current Science 106 ( 4 ) 504 - 505 2014
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Matsuoka, M. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Journal of Asian Ceramic Societies 2 ( 3 ) 199 - 203 2014 [Reviewed]
DOI Web of Science Scopus CiNii Research
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Informa UK Limited Joint Work
AbstractStudies on the dispersion of carbon nanotubes (CNTs) in silicon nitride (Si3N4) ceramics to provide the latter with electrical conductivity have been carried out in recent years. The density and the strength of Si3N4 ceramics were degraded, however, because the CNTs prevented Si3N4 from densifying. The CNTs disappeared after firing at high temperatures owing to the reaction between CNTs and Si3N4 or SiO2, or both Si3N4 and SiO2. In order to improve the density and suppress the reaction, sintering aids for lower-temperature densification of Si3N4 are needed. In this study, we added HfO2 as a sintering aid to a Si3N4–Y2O3–Al2O3–AlN–TiO2 system to fabricate CNT-dispersed Si3N4 ceramics at lower temperatures. Furthermore, bead milling was applied to disperse the CNTs homogeneously. Agglomerates of CNTs were pulverized by bead milling without obvious changes in morphology to eliminate larger fracture origins in CNT-dispersed ceramics. As a result of both the addition of HfO2 and bead milling, we successfully fabricated dense CNT-dispersed Si3N4 ceramics with high strength and electrical conductivity.
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Matsuoka, M. and Tatami, J. and Wakihara, T.
Ceramic Transactions 243 117 - 120 2014
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Fabrication of Si<sub>3</sub>N<sub>4</sub> Ceramics Using Raw Materials Prepared by Bead Milling
Tatami Junichi, Fukuda Shinya
Journal of the Society of Powder Technology, Japan 51 ( 6 ) 430 - 435 2014 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Society of Powder Technology, Japan Joint Work
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多々見 純一, 中野 裕美
粉砕 = The micromeritics ( 57 ) 43 - 50 2014 [Reviewed]
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ホソカワミクロン Joint Work
コレクション : 国立国会図書館デジタルコレクション > 電子書籍・電子雑誌 > その他
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Yokoyama T., Meguro T., Kato K., Okazaki S., Ito D., Tatami J., Wakihara T., Komeya K.
JOURNAL OF ELECTROCERAMICS 31 ( 3-4 ) 353 - 359 2013.12 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microstructure of seal formed between a Nb wire and an Al2O3 capillary melted by YAG laser radiation
Honma Takuya, Kamata Hiroshi, Tatami Junichi
CERAMICS INTERNATIONAL 39 ( 5 ) 4861 - 4875 2013.7 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Cracks occasionally develop inside the glass frit, the sealing material used in ceramic metal-halide lamps that employ polycrystalline alumina as the arc-tube material, although the rate at which these cracks develop is low. Therefore, we proposed a new method to stop their development. Our method did not make use of a glass frit and involved the formation of a seal between the Nb wire and the Al 2 O 3 capillary melted by the radiant energy from a YAG laser. However, cracks or voids developed inside the melted Al 2 O 3 capillary. Therefore, in order to control the Al 2 O 3 microstructure inside the melted Al 2 O 3 capillary and thus to obtain a better seal, grain growth was suppressed by combining the processes of annealing after melting and grain-boundary deposition of Ta. The Al 2 O 3 microstructure could be controlled by these factors. Thus, optimized conditions for forming the seal were achieved.
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Top-down Tuning of Nanosized Zeolites by Bead-milling and Recrystallization
Wakihara Toru, Tatami Junichi
Journal of the Japan Petroleum Institute 56 ( 4 ) 206 - 213 2013.7 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：The Japan Petroleum Institute Joint Work
The fact that zeolites with high external surface area allow diffusing reactants greater access to active sites, has led to interest in the preparation of nanosized zeolites. The organic template-free synthesis of nanosized zeolite has been a subject of special importance for scientific and industrial applications. Thus far, most research has focused on a bottom-up approach for the fabrication of nano-zeolites, that is, control of zeolite nucleation and crystal growth during hydrothermal synthesis. This review summarizes a new method for the top-down production of nano-zeolite powder by first milling the zeolite to produce nanoparticles. This technique destroys the outer portion of the zeolite framework thereby decreasing its ion-exchange properties and catalytic activity. To remedy this, the damaged portions were recrystallized using a dilute aluminosilicate or silicate solution after bead-milling. The combined bead-milling and post-milling recrystallization yielded nano-zeolites with high crystallinity. The nanosized powders showed higher ion-exchange properties for zeolite A and higher catalytic activity for ZSM-5, respectively.
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多々見 純一
粉体技術 / 日本粉体工業技術協会「粉体技術」編集委員会 編 5 ( 7 ) 627 - 632 2013.7
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本粉体工業技術協会 Single Work
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Influence of crystallization inside glass frit on seal stress in ceramic metal halide lamps
Honma Takuya, Kamata Hiroshi, Tatami Junichi
CERAMICS INTERNATIONAL 39 ( 3 ) 2767 - 2774 2013.4 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Ceramic metal halide lamps use polycrystalline aluminum oxide as an arc tube material; cracks inside the glass frit—used as the seal material—have been known to occur occasionally. This study measured the stress on the lamp seals caused by changes in the cooling rate during the sealing process by a 2D stress measurement method. Seal stress decreased with reducing cooling rate. Therefore, we discuss the influences of the glass frit's microstructure and the coefficients of thermal expansion (glass frit, capillary, and Nb wire) on the seal stress. The coefficient of thermal expansion of the annealed glass frit was essentially closer to those of the capillary and Nb wire, while that of the rapidly cooled glass frit differed greatly. Moreover, the glass frit of the rapidly cooled lamp seal contained only an amorphous phase (Dy, Si, Al, and O), while the glass frit of the annealed lamp seal contained both an amorphous phase (Dy, Si, Al, and O) and a crystalline one (Dy 2 SiO 5 and Al 2 O 3 ). Fracture toughness was found to be larger in the crystals than in the amorphous phase area. Moreover, it was larger in the area where crystalline Dy 2 SiO 5 and Al 2 O 3 were present compared to the area where only crystalline Dy 2 SiO 5 was present. Thus, the coefficient of thermal expansion of the glass frit containing the crystalline phase was found to influence the seal stress. Furthermore, the crystallization in the glass frit was found to influence crack propagation. Therefore, formation of cracks inside the glass frit can be prevented by optimizing these factors, which can be achieved by changing the cooling rate in the sealing process without changing the specifications of the glass frit (composition, composition ratio, etc.).
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ビーズミル粉砕とポスト処理を組み合わせたゼオライトナノ粉体の新規調製法
脇原 徹, 多々見 純一
工業材料 = Engineering materials 61 ( 2 ) 34 - 37 2013.2
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日刊工業出版プロダクション ; 1955- Joint Work
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Analysis and Control of Sintering Process of Ceramics Using Master Sintering Curves
TATAMI Junichi
48 ( 1 ) 22 - 27 2013.1
Language：English Publishing type：Research paper (scientific journal) Single Work
Other Link： https://ci.nii.ac.jp/naid/10031155624
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Honma Takuya, Sasaki Ikue, Tamura Nobuhiro, Tatami Junichi, Fujichika Shinichiro, Komeya Katsutoshi … Show more authors
Honma Takuya, Sasaki Ikue, Tamura Nobuhiro, Tatami Junichi, Fujichika Shinichiro, Komeya Katsutoshi, Meguro Takeshi Hide authors
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY 10 ( 2 ) 348 - 353 2013 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>To fabricate functionally graded materials, a highly concentrated slurry of <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub></jats:roman></jats:styled-content>‐<jats:styled-content style="fixed-case"><jats:roman>Mo</jats:roman></jats:styled-content> system was prepared and centrifugal force was applied in an attempt to achieve a graded composition. Subsequently, we formed a homogeneous green body with compositional gradation by floc‐casting at 80°C, which was then fired at 1750°C for 10 min in <jats:styled-content style="fixed-case">Ar</jats:styled-content>. The sintered body had compositional ratios of <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub></jats:roman></jats:styled-content> and <jats:styled-content style="fixed-case"><jats:roman>Mo</jats:roman></jats:styled-content> as well as electrical conductivities that changed gradually along the direction of centrifugal force. The results demonstrate that centrifugation and control of slurry characteristics such as flocculation are effective in fabricating functionally graded <jats:styled-content style="fixed-case"><jats:roman>SiO<jats:sub>2</jats:sub></jats:roman></jats:styled-content>‐<jats:styled-content style="fixed-case"><jats:roman>Mo</jats:roman></jats:styled-content> materials.</jats:p>
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Wakihara, T. and Ichikawa, R. and Tatami, J. and Komeya, K. and Meguro, T.
Ceramic Engineering and Science Proceedings 33 ( 8 ) 129 - 134 2013 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Sato Kaku, Wakihara Toru, Kohara Shinji, Ohara Koji, Tatami Junichi, Endo Akira, Inagaki Satoshi, K … Show more authors
Sato Kaku, Wakihara Toru, Kohara Shinji, Ohara Koji, Tatami Junichi, Endo Akira, Inagaki Satoshi, Kawamura Izuru, Naito Akira, Kubota Yoshihiro Hide authors
JOURNAL OF PHYSICAL CHEMISTRY C 116 ( 48 ) 25293 - 25299 2012.12 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Joint Work
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多々見 純一
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 47 ( 12 ) 908 - 912 2012.12
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Single Work
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TATAMI Junichi, OHNO Kensuke, WAKIHARA Toru, MEGURO Takeshi, KOMEYA Katsutoshi
Journal of Smart Processing 1 ( 5 ) 237 - 241 2012.9 [Reviewed]
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Smart Processing Society for Materials, Environment & Energy (High Temperature Society of Japan) Joint Work
Carbon black / phenol resin nanocomposite particles were prepared by mechanical treatment. Bulk bodies were fabricated using these nanocomposite particles by uniaxial pressing and slip casting technique to control the electrical conductivity. Scanning electron microscope (SEM) observation showed dense and thick layer of carbon black were formed on the phenol resin particle by mechanical treatment. electrical conductivity of the bulk body prepared using hollow carbon black was higher than that using dense carbon black. The bulk body fabricated by slip casting technique showed higher electrical conductivity than that by uniaxial pressing because of development of percolation structure due to higher coordination number of nanocomposite particles.
Other Link： https://ci.nii.ac.jp/naid/10031008775
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SHYLOVA Svitlana, MEGURO Takeshi, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi
材料の科学と工学 = Materials science and technology 49 ( 4 ) 167 - 174 2012.8 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10030957245
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Preparation of nano-zeolite X by bead-milling and post-milling recrystallization
Wakihara, T; Sato, K; Sato, K; Tatami, J; Kohara, S; Komeya, K; Meguro, T
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 120 ( 1404 ) 341 - 343 2012.8
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
A top-down approach has been applied for the preparation of nano zeolite X using a combination of bead milling and post-milling recrystallization. This gives nano zeolite X approximately 60 nm in size with high crystallinity without using specific organic compounds. Pair distribution function analysis by high-energy X-ray diffraction showed that the ring structure of zeolite framework is distorted and/or destroyed by bead milling, and the crystallinity returned to close to the original level after recrystallization treatment.
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SHYLOVA Svitlana, MEGURO Takeshi, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi
49 ( 3 ) 115 - 124 2012.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10030798333
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SHYLOVA Svitlana, MEGURO Takeshi, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi
49 ( 3 ) 125 - 131 2012.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10030798351
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Effect of TiO2 addition on thermal and mechanical properties of Y-Si-Al-O-N glasses
Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kidari Abdessamad, Hampshire Stua … Show more authors
Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kidari Abdessamad, Hampshire Stuart, Pomeroy Michael J. Hide authors
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 32 ( 6 ) 1157 - 1161 2012.6 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Y–Si–Al–O–N glasses are intergranular phases in silicon nitride based ceramics in which the composition and volume fraction of oxynitride glass phases determine the sintering/shrinkage behaviour. Several investigations on oxynitride glass formation and properties have shown that addition of nitrogen increases glass transition and softening temperatures, viscosity, elastic modulus and hardness. In the present study, effect of TiO2 addition on thermal and mechanical properties of Y–Si–Al–O–N glasses is investigated since the most typical Si3N4 ceramics for bearing applications are fabricated using a Si3N4–Y2O3–Al2O3–TiO2–AlN system. Addition of TiO2 is effective in preparing Y–Si–Al–O–N glasses with lower glass transition temperatures and with higher hardness.
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Kouichi Yasuda, Tomitsugu Taguchi, Junichi Tatami, Yohtaro Matsuo
Ceramic Transactions 2012.4 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：John Wiley & Sons, Ltd Joint Work
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Carrier Scattering at Grain Boundary in Textured ZnO
KINEMUCHI Yoshiaki, KAGA Hisashi, NAKANO Hiromi, TANAKA Satoshi, UEMATSU Keizo, TATAMI Junichi, WAT … Show more authors
KINEMUCHI Yoshiaki, KAGA Hisashi, NAKANO Hiromi, TANAKA Satoshi, UEMATSU Keizo, TATAMI Junichi, WATARI Koji Hide authors
Ceramics Japan : Bulletin of the Ceramic Society of Japan 47 ( 4 ) 275 - 279 2012.4
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10031155534
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脇原 徹, 多々見 純一
機能材料 32 ( 4 ) 20 - 25 2012.4
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：シーエムシー出版 Joint Work
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多々見 純一, 米屋 勝利
Ceramics Japan = セラミックス : bulletin of the Ceramic Society of Japan 47 ( 1 ) 20 - 24 2012.1
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本セラミックス協会 Joint Work
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Matsuoka Mitsuaki, Yoshio Sara, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi … Show more authors
Matsuoka Mitsuaki, Yoshio Sara, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Transactions of the Materials Research Society of Japan 37 ( 1 ) 11 - 14 2012
Language：English Publishing type：Research paper (scientific journal) Publisher：一般社団法人 日本MRS Joint Work
The preparation of electrically conductive silicon nitride (Si<sub>3</sub>N<sub>4</sub>) ceramics by dispersing carbon nanotubes (CNTs) has been studied in the recent years. However, the density and strength of Si<sub>3</sub>N<sub>4</sub> ceramics was found to deteriorate and the CNTs disappeared after firing at high temperatures because CNTs prevent Si<sub>3</sub>N<sub>4</sub> from densification and there is a possibility that the CNTs reacted with the Si<sub>3</sub>N<sub>4</sub> or SiO<sub>2</sub>. To prevent the CNTs from reacting and disappearing, low temperature densification is required. In this study, HfO<sub>2</sub> was added to a Si<sub>3</sub>N<sub>4</sub>-Y<sub>2</sub>O<sub>3</sub>-Al<sub>2</sub>O<sub>3</sub>-AlN system to fabricate CNT-dispersed Si<sub>3</sub>N<sub>4</sub> ceramics at low temperatures. As a result, a sample to which HfO<sub>2</sub> had been added and which was fired at lower temperatures showed higher electrical conductivity and higher bending strength. It was also observed that the mechanical and electrical properties of the ceramics depended on the quantity of added CNTs.
Other Link： https://ci.nii.ac.jp/naid/130003399035
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Pore elimination process of Si<SUB>3</SUB>N<SUB>4</SUB> ceramics in sintering
SANO YUKI, TATAMI JUNICHI, WAKIHARA TORU, KOMEYA KATSUTOSHI, MEGURO TAKESHI, YOKOUCHI MASAHIRO
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2012 ( 0 ) 113 - 113 2012
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006977614
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Preparation of nanosized ZSM-5 zeolite catalyst by bead milling and recrystallization technique.
Wakihara Toru, Ihara Akio, Inagaki Satoshi, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kubo … Show more authors
Wakihara Toru, Ihara Akio, Inagaki Satoshi, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kubota Yoshihiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2012 ( 0 ) 557 - 557 2012
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006983663
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Matsuoka, M. and Yoshio, S. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Journal of the Korean Ceramic Society 49 ( 4 ) 333 - 336 2012 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Preparation of nano-zeolite X by bead-milling and post-milling recrystallization
Wakihara, Toro and Sato, Koki and Sato, Kaku and Tatami, Junichi and Kohara, Shinji and Komeya … Show more authors
Wakihara, Toro and Sato, Koki and Sato, Kaku and Tatami, Junichi and Kohara, Shinji and Komeya, Katsutoshi and Meguro, Takeshi Hide authors
Journal of the Ceramic Society of Japan 120 ( 1404 ) 341 - 343 2012 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Preparation of Ca-alpha SiAlON powder by reduction-nitridation in a gas mixture of C3H8 and NH3
Hotta, Mikinori and Kita, Hideki and Yamakawa, Tomohiro and Tatami, Junichi and Komeya, Katsuto … Show more authors
Hotta, Mikinori and Kita, Hideki and Yamakawa, Tomohiro and Tatami, Junichi and Komeya, Katsutoshi and Meguro, Takeshi Hide authors
Journal of the Ceramic Society of Japan 120 ( 1400 ) 155 - 157 2012 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Electrical conductive CNT dispersed Si<inf>3</inf>N<inf>4</inf> ceramics
Tatami, J.
Nanoparticle Technology Handbook 498 - 500 2012
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Preparation of Nanosized ZSM-5 Zeolite Catalyst by Bead Milling and Recrystallization Technique
WAKIHARA TORU, TATAMI JUNICHI, INAGAKI SATOSHI, KUBOTA YOSHIHIRO
53 ( 7 ) 415 - 419 2011.12
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10030178842
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Bead-Milling and Post-Milling Recrystallization
Wakihara Toru, Tatami Junichi
28 ( 4 ) 131 - 137 2011.12 [Invited]
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Association of Zeolite Joint Work
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Kobayashi Ryota, Tatami Junichi, Chen I. Wei, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Got … Show more authors
Kobayashi Ryota, Tatami Junichi, Chen I. Wei, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Goto Takashi, Tu Rong Hide authors
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 94 ( 12 ) 4150 - 4153 2011.12 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>Dense <jats:styled-content style="fixed-case"><jats:roman>AlN–SiC</jats:roman></jats:styled-content> solid solution ceramics with 25–75 mol% <jats:styled-content style="fixed-case"><jats:roman>AlN</jats:roman></jats:styled-content> were fabricated by spark plasma sintering using hexagonal <jats:styled-content style="fixed-case"><jats:roman>SiC</jats:roman></jats:styled-content> and <jats:styled-content style="fixed-case"><jats:roman>AlN</jats:roman></jats:styled-content> powders without additives. The bending strength reaches 800 MPa at room temperature with a fracture toughness of about 5 MPa·m<jats:sup>1/2</jats:sup>. The high bending strength can be retained at high temperatures, maintaining over 400 MPa at 1700°C.</jats:p>
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Dispersion of carbon nanotubes in ethanol by a bead milling process
Yoshio Sara, Tatami Junichi, Yamakawa Tomohiro, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, A … Show more authors
Yoshio Sara, Tatami Junichi, Yamakawa Tomohiro, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Aramaki Kenji, Yasuda Kouichi Hide authors
CARBON 49 ( 13 ) 4131 - 4137 2011.11 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Carbon nanotubes (CNTs) were dispersed in ethanol by bead milling to form a CNT suspension. The size and shape of the CNTs were not changed after bead milling. The Brownian motion of the CNTs was observed by an optical microscope. It was shown by analysis off the trajectory of individual CNTs that the diffusion coefficient of their translational Brownian motion was 4.5 × 10−13 m2 s−1. The ratio of the particle mobilities due to drift flow and diffusion flow was 2.4, which is almost the same as for a high-molecular-weight protein. Shear thinning occurred in the CNT suspension, which means that the CNTs were oriented in the suspension under a high shear rate at low viscosity. The intrinsic viscosity for shear rates of 0 and ∞ agreed with those calculated using Simha’s equation and Leal and Hinch’s equation, respectively. Based on the experimental results, the CNTs were found to be well dispersed as isolated and nanosized rod-like particles in the suspension. CNT-dispersed Si3N4 ceramics were fabricated using the CNT suspensions. As a result, the bead milling improved the bend strength of the CNT Si3N4 ceramics compared with the wet ball milling because granules of CNTs were eliminated by the bead milling.
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Top-Down Tuning of Nanosized ZSM-5 Zeolite Catalyst by Bead Milling and Recrystallization
Wakihara Toru, Ihara Akio, Inagaki Satoshi, Tatami Junichi, Sato Kaku, Komeya Katsutoshi, Meguro Ta … Show more authors
Wakihara Toru, Ihara Akio, Inagaki Satoshi, Tatami Junichi, Sato Kaku, Komeya Katsutoshi, Meguro Takeshi, Kubota Yoshihiro, Nakahira Atsushi Hide authors
CRYSTAL GROWTH & DESIGN 11 ( 11 ) 5153 - 5158 2011.11 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work
Zeolites with high external surface area allow diffusing reactants greater access to catalytically active sites, which has led to interest in the preparation of nanosized zeolites. In this study, a...
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多々見 純一, 米屋 勝利
マテリアルインテグレーション = Materials integration 24 ( 11 ) 52 - 55 2011.11
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ティー・アイ・シィー Joint Work
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Sato Kaku, Wakihara Toru, Kohara Shinji, Tatami Junichi, Inagaki Satoshi, Kubota Yoshihiro, Komeya … Show more authors
Sato Kaku, Wakihara Toru, Kohara Shinji, Tatami Junichi, Inagaki Satoshi, Kubota Yoshihiro, Komeya Katsutoshi, Meguro Takeshi Hide authors
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 119 ( 1391 ) 605 - 608 2011.7 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Different types of amorphous solids derived from Na- and K-zeolite A were prepared by mechanical or post-mechanical thermal treatments and changes in the atomic arrangement of these solids were characterized by high-energy X-ray diffraction (HEXRD). HEXRD measurements revealed that the structures of the amorphous solids after mechanical and post-mechanical thermal amorphization were different from one another. These amorphous solids were recrystallized to zeolite and the effect of the atomic arrangement of the raw materials on zeolite crystallization behavior was investigated. It was also shown that the recrystallization behavior of amorphous solids back to zeolite is different in mechanically and post-mechanical thermally amorphized samples. This arises from the difference in the medium range order in the amorphous solids; that is, post-mechanical thermally amorphized samples were more able to change into dense phases since the ring structure of zeolite A was more distorted and/or destroyed than in only mechanically amorphized samples.
Other Link： https://ci.nii.ac.jp/naid/130000784439
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Wakihara Toru, Ichikawa Ryuma, Tatami Junichi, Endo Akira, Yoshida Kaname, Sasaki Yukichi, Komeya K … Show more authors
Wakihara Toru, Ichikawa Ryuma, Tatami Junichi, Endo Akira, Yoshida Kaname, Sasaki Yukichi, Komeya Katsutoshi, Meguro Takeshi Hide authors
CRYSTAL GROWTH & DESIGN 11 ( 4 ) 955 - 958 2011.4 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work
Organic template-free synthesis of nano-zeolite has been an important subject of both scientific and industrial applications. Most research has focused on the fabrication of nano-zeolite by a bottom up approach, that is, control of zeolite nucleation and crystal growth during the hydrothermal synthesis. This communication reports a new method for the production of nano-zeolite powder by a top-down approach. In this study, the zeolite was first milled to produce a nanopowder. This technique can cause destruction of the outer portion of the zeolite framework and hence cause pore blocking, which deactivates various properties of the zeolite. To remedy this, the damaged part was recrystallized using a dilute aluminosilicate solution after bead milling. As a result of the combination of bead milling and postmilling recrystallization, nano-zeolite A (LTA type zeolite) about 50 nm in size with high crystallinity was successfully obtained.
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米屋 勝利, 多々見 純一
未来材料 = Expected materials for the future 11 ( 3 ) 16 - 23 2011.3
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：エヌ・ティー・エス Joint Work
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Hotta Mikinori, Hojo Junichi, Komeya Katsutoshi, Tatami Junichi, Meguro Takeshi, Masuda Hirohisa, M … Show more authors
Hotta Mikinori, Hojo Junichi, Komeya Katsutoshi, Tatami Junichi, Meguro Takeshi, Masuda Hirohisa, Morinaga Kenji, Cheng Yi-Bing Hide authors
MATERIALS LETTERS 65 ( 1 ) 116 - 118 2011.1 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Ca-α SiAlON powders were prepared by carbothermal reduction–nitridation of CaO–Al 2 O 3 –SiO 2 glasses at 1450 °C for 2 h in nitrogen. The content of Ca-α SiAlON phase was 65–81% in the products, and the other phases were AlN and β-SiAlON. The products contained hollow spheres with the size of around 5 μm in diameter. The particle morphology was almost identical to that of Ca-α SiAlON prepared from CaCO 3 –Al 2 O 3 –SiO 2 powder mixtures.
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Yoshio Sara, Tatami Junichi, Wakihara Toru, Yamakawa Tomohiro, Nakano Hiromi, Komeya Katsutoshi, Me … Show more authors
Yoshio Sara, Tatami Junichi, Wakihara Toru, Yamakawa Tomohiro, Nakano Hiromi, Komeya Katsutoshi, Meguro Takeshi Hide authors
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 119 ( 1385 ) 70 - 75 2011.1 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Electrically conductive carbon nanotube (CNT)-dispersed ceramics with high strength were fabricated by varying the CNT quantity and the firing temperature. We investigated the effect of these factors on density, electrical conductivity, bending strength, and microstructure of the developed ceramics. The relative density of the CNT dispersed Si<sub>3</sub>N<sub>4</sub> ceramics was higher than 90% except for the sample containing less than 1 wt % of CNTs and fired at a temperature of 1800°C. It was confirmed that CNTs exist in the samples with a higher density. The pullout length of CNTs on the fracture surface in samples fired at higher temperatures was shorter because of the degradation of the CNTs. By TEM observation, CNTs were found to exist in the grain boundary in the Si<sub>3</sub>N<sub>4</sub> ceramics, and their diameter was found to be almost the same as that of raw CNTs. Electrical conductivity appeared in the samples by adding CNTs more than 1 wt % though the sample by adding 0.5 wt % CNTs was insulator. The electrical conductivities of the samples increased with an increase in the firing temperature, which was explained by the grain growth of β-Si<sub>3</sub>N<sub>4</sub>. The bending strength of the samples with 1 wt % of CNTs was as high as that of samples without CNTs. Thus, CNT-dispersed Si<sub>3</sub>N<sub>4</sub> ceramics having both electrical conductivity and a higher bending strength were obtained by controlling the CNT quantity and the firing temperature.
Other Link： https://ci.nii.ac.jp/naid/130000420851
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Tatami Junichi, Noguchi Makoto, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
ADVANCED PROCESSING AND MANUFACTURING TECHNOLOGIES FOR STRUCTURAL AND MULTIFUNCTIONAL MATERIALS V 32 ( 8 ) 177 - 182 2011
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Matsuoka Mitsuaki, Yoshio Sara, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi … Show more authors
Matsuoka Mitsuaki, Yoshio Sara, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 283 - 283 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
CNT-dispersed Si<SUB>3</SUB>N<SUB>4</SUB> ceramics was fabricated by adding HfO2 as sintering aids. As a result, the sample by adding HfO<SUB>2</SUB> fired at lower temperatures showed higher bending strength and higher electrical conductivity because HfO<SUB>2</SUB> promoted the densification of Si<SUB>3</SUB>N<SUB>4</SUB> and prevented CNT from disappearance. CNT-dispersed Si<SUB>3</SUB>N<SUB>4</SUB> ceramics by adding HfO<SUB>2</SUB> added indicated higher bending strength and higher electrical conductivity than those by adding TiO<SUB>2</SUB>.
Other Link： https://ci.nii.ac.jp/naid/130006976957
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FABRICATION OF CNT-DISPERSED Si3N4 CERAMICS BY MECHANICAL DRY MIXING TECHNIQUE
Hashimoto Atsushi, Yoshio Sara, Tatami Junichi, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi, Me … Show more authors
Hashimoto Atsushi, Yoshio Sara, Tatami Junichi, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
ADVANCED PROCESSING AND MANUFACTURING TECHNOLOGIES FOR STRUCTURAL AND MULTIFUNCTIONAL MATERIALS V 32 ( 8 ) 83 - 88 2011
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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ELECTRICAL CONDUCTIVE CNT-DISPERSED Si3N4 CERAMICS WITH DOUBLE PERCOLATION STRUCTURE
Yoshio Sara, Tatami Junichi, Wakihara Toru, Yamakawa Tomohiro, Komeya Katsutoshi, Meguro Takeshi
ADVANCED PROCESSING AND MANUFACTURING TECHNOLOGIES FOR STRUCTURAL AND MULTIFUNCTIONAL MATERIALS V 32 ( 8 ) 77 - 82 2011
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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yoshio sara, Tatami Junichi, Wakihara Toru, Yamakawa Tomohiro, Nakano Hiromi, Komeya Katsutoshi, Me … Show more authors
yoshio sara, Tatami Junichi, Wakihara Toru, Yamakawa Tomohiro, Nakano Hiromi, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 650 - 650 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Electrically conductive CNT-dispersed Si3N4 ceramics with high strength were fabricated by varying the CNT quantity and the firing temperature. By TEM observation, CNTs were found to exist in the grain boundary in the Si3N4 ceramics, and their diameter was found to be almost the same as that of raw CNTs. The electrical conductivities of the samples increased with an increase in the firing temperature, which was explained by the grain growth of Si3N4. The bending strength of the samples with 1 wt% of CNTs was as high as that of samples without CNTs. Thus, CNT-dispersed Si3N4 ceramics having both electrical conductivity and a higher bending strength were obtained by controlling the CNT quantity and the firing temperature.
Other Link： https://ci.nii.ac.jp/naid/130006979906
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Synthesis of B<SUB>4</SUB>CN<SUB>4</SUB> and BN by nitriding of B<SUB>4</SUB>C
Mine Keita, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 313 - 313 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976212
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Synthesis and morphological control of Al<SUB>5</SUB>C<SUB>3</SUB>N
Hironaka Masaki, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 274 - 274 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976915
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Single-phase synthesis of Al<SUB>5</SUB>C<SUB>3</SUB>N
Hironaka Masaki, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 591 - 591 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978806
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Yonashiro Ken, Tatami Junichi, Wakihara Toru, Komeya katsutoshi, Meguro Takeshi, Fukunaga Yutaka, K … Show more authors
Yonashiro Ken, Tatami Junichi, Wakihara Toru, Komeya katsutoshi, Meguro Takeshi, Fukunaga Yutaka, Kanechika Yukihiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 764 - 764 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979534
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Yonashiro Ken, Tatami Junniti, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Fukunaga Yutaka, M … Show more authors
Yonashiro Ken, Tatami Junniti, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Fukunaga Yutaka, Muneoka Takatoshi, Watanabe Kazutaka, Kanechika Yukihiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 278 - 278 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976908
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Tatami Junichi, Kubota Kenichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 766 - 766 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006980071
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Uemura Masaaki, Tatami Junichi, Wakihara Toru, Komeya Katutoshi, Meguro Takeshi, Sugai Atsushi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 177 - 177 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975514
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Ohnishi Masahiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 194 - 194 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975607
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Changes in the Local Structure of a Zeolite through Milling Process Observed by Electron Microscopy
Wakihara Toru, Tatami Junichi, Ichikawa Ryuma, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 334 - 334 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976970
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Kayama Hiroaki, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Hattori Tomoya
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 179 - 179 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975517
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Preparation of TiN nanoparticle-dispersed Si<SUB>3</SUB>N<SUB>4</SUB> ceramics by wet jet milling
Kayama Hiroaki, Tatami Junnichi, Wakihara Toru, Komeya Katutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 280 - 280 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976881
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Tatami Junichi, Noguchi Makoto, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 648 - 648 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Nanocomposite particles composed of Y2O3 and Al2O3 nanoparticles as sintering aids and submicron Si3N4 particles were prepared by mechanical powder composite process to control microstructure of Si3N4 ceramics.b-Si3N4 grains in the ceramics fabricated using nanocposite particles prepared by mechanical powder composite process were more elongated than that by wet ball mixing process. the developed Si3N4 powder by dry mechanical treatment showed higher fracture toughness due to the more elongated b-Si3N4 grains.
Other Link： https://ci.nii.ac.jp/naid/130006979905
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Hashimoto Atsushi, Tatami Junichi, Nakano Hiromi, Wakihara Toru, Yoshio Sara, Komeya Katsutoshi, Me … Show more authors
Hashimoto Atsushi, Tatami Junichi, Nakano Hiromi, Wakihara Toru, Yoshio Sara, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 649 - 649 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979904
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Hashimoto Atsushi, Tatami Junichi, Meguro Takeshi, Wakihara Toru, Komeya Katsutoshi, Nakano Hiromi, … Show more authors
Hashimoto Atsushi, Tatami Junichi, Meguro Takeshi, Wakihara Toru, Komeya Katsutoshi, Nakano Hiromi, Inoue Maki, Konishi Yukihiro, Suzuki Toshimasa Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 175 - 175 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975512
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Synthesis of silicon-silicon nitride powder from waste sludge
Hosoya Ryouta, Tatami Jyunichi, Wakihara Tooru, Komeya Katsutosi, Meguro Takesi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 311 - 311 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Use of industrial waste sludge waste silicon, silicon nitride powders were synthesized by changing the criteria for a variety of nitride.
Other Link： https://ci.nii.ac.jp/naid/130006976246
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Matsuoka Mitsuaki, Yoshio Sara, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 315 - 315 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
CNT-dispersed Si<SUB>3</SUB>N<SUB>4</SUB> ceramics were fabricated by bead milling and by adding HfO<SUB>2</SUB> as a sintering aid for lower temperature densification. As a result, the samples by adding HfO<SUB>2</SUB> fired at lower temperatures showed higher bending strength and higher electrical conductivity because HfO<SUB>2</SUB> promoted the densification of Si<SUB>3</SUB>N<SUB>4</SUB> and prevented CNT from disappearance. CNT-dispersed Si<SUB>3</SUB>N<SUB>4</SUB> ceramics prepared by bead milling indicated higher bending strength than those by ball milling because of pulverization of agglomerations of CNTs by bead milling.
Other Link： https://ci.nii.ac.jp/naid/130006977054
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Catalytic properties of zeolite nanoparticles fabricated by bead milling method
Sato Koki, Wakihara Toru, Inagaki Satoshi, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kubot … Show more authors
Sato Koki, Wakihara Toru, Inagaki Satoshi, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kubota Yoshihiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 39 - 39 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976929
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Fabrication of Si<SUB>3</SUB>N<SUB>4</SUB> ceramics using raw materials prepared by bead milling
Tatami Junichi, Fukuda Shinya, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 694 - 694 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979294
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Brownian motion of carbon nanotubes dispersed in ethanol
Tatami Junichi, Yoshio Sara, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Yasuda Kouichi, Aram … Show more authors
Tatami Junichi, Yoshio Sara, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Yasuda Kouichi, Aramaki Kenji Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 388 - 388 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976919
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Uoji Takuya, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 312 - 312 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976244
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Fabrication and evaluation of YAG/beta-SiAlON composites
Ito Akihiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 674 - 674 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978957
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Otake Hiroshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Sugai Atsushi, Yam … Show more authors
Otake Hiroshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Sugai Atsushi, Yamaguchi Hiroshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 191 - 191 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975616
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Otake Hiroshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Sugai Atsushi, Yam … Show more authors
Otake Hiroshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Sugai Atsushi, Yamaguchi Hiroshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2011 ( 0 ) 285 - 285 2011
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976953
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Yoshio, S. and Tatami, J. and Wakihara, T. and Yamakawa, T. and Komeya, K. and Meguro, T.
Ceramic Engineering and Science Proceedings 32 ( 8 ) 77 - 82 2011
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Tatami, J. and Noguchi, M. and Nakano, H. and Wakihara, T. and Komeya, K. and Meguro, T.
Ceramic Engineering and Science Proceedings 32 ( 8 ) 177 - 182 2011
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Fabrication of cnt-dispersed Si<inf>3</inf>N<inf>4</inf> ceramics by mechanical dry mixing technique
Hashimoto, A. and Yoshio, S. and Tatami, J. and Nakano, H. and Wakihara, T. and Komeya, K. and Megu … Show more authors
Hashimoto, A. and Yoshio, S. and Tatami, J. and Nakano, H. and Wakihara, T. and Komeya, K. and Meguro, T. Hide authors
Ceramic Engineering and Science Proceedings 32 ( 8 ) 83 - 88 2011
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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粉砕および再結晶化プロセスを組み合わせたゼオライトナノ粒子の新規調製法
脇原 徹, 多々見 純一
ゼオライト = Zeolite 28 ( 4 ) 131 - 137 2011
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ゼオライト学会 Joint Work
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Changes in the medium-range order of zeolite A by mechanical and thermal amorphization
Wakihara Toru, Sato Kaku, Kohara Shinji, Sankar Gopinathan, Tatami Junichi, Komeya Katsutoshi, Megu … Show more authors
Wakihara Toru, Sato Kaku, Kohara Shinji, Sankar Gopinathan, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, MacKenzie Kenneth J. D. Hide authors
MICROPOROUS AND MESOPOROUS MATERIALS 136 ( 1-3 ) 92 - 96 2010.12 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Crystalline zeolite A was amorphized by mechanical and thermal treatments, and the resulting changes in the atomic arrangement are characterized by HEXRD, Al-27 MAS NMR and Raman spectroscopy. HEXRD measurements revealed that the 6R and 8R rings are distorted and/or destroyed, while the 4R ring is preserved during mechanical treatment, but all rings are distorted and/or destroyed by thermal treatment. Data from Al-27 MAS NMR and Raman spectroscopy also support these results. Furthermore, recrystallization behavior is found to be different between mechanically and thermally amorphized solids. (C) 2010 Elsevier Inc. All rights reserved.
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Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Ta … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Takashi Hide authors
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 93 ( 12 ) 4026 - 4029 2010.12 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>Dense and elemental homogeneous 2H AlN–SiC solid solution doped with Al and C was fabricated by using spark plasma sintering. The <jats:italic>p</jats:italic>‐type electrical conduction of the sample was confirmed by measurements of electrical conductivities and Seebeck coefficient. Dopant profiling of the sample by scanning nonlinear dielectric microscopy showed that the AlN–SiC grains respond to <jats:italic>p</jats:italic>‐type electrical conduction. These results indicated that added Al and C were dissolved to the grains and acted as <jats:italic>p</jats:italic>‐type dopants. In contrast, the grain boundaries did not show any response, suggesting the presence of depletion layer in the boundary.</jats:bold> </jats:p>
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Fabrication of Fine Zeolite with Improved Catalytic Properties by Bead Milling and Alkali Treatment
Wakihara Toru, Sato Koki, Inagaki Satoshi, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kubot … Show more authors
Wakihara Toru, Sato Koki, Inagaki Satoshi, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kubota Yoshihiro Hide authors
ACS APPLIED MATERIALS & INTERFACES 2 ( 10 ) 2715 - 2718 2010.10 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work
Zeolites with high external surface area allow diffusing reactants greater access to catalytically active sites, which has lead to interest in the preparation of nano-zeolites. In this study, a top-down approach has been used, first milling the zeolite to produce a fine powder. This technique can cause destruction of the outer portion of the zeolite framework, which deactivates the catalyst. To remedy this, the damaged part was removed using an alkaline solution after bead milling treatment. As a result, the designed zeolite powder yielded almost twice the amount of benzene compared with the raw zeolite when cumene was cracking into benzene and propylene.
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Hotta Mikinori, Tatami Junichi, Zhang Cheng, Komeya Katsutoshi, Meguro Takeshi, Terner Mark R., Che … Show more authors
Hotta Mikinori, Tatami Junichi, Zhang Cheng, Komeya Katsutoshi, Meguro Takeshi, Terner Mark R., Cheng Yi-Bing Hide authors
CERAMICS INTERNATIONAL 36 ( 5 ) 1553 - 1559 2010.7 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract The formation process of hollow spheres composed of nanosized Ca-α SiAlON particles was investigated using SiO 2 starting powders with different characteristics in particle size, shape and crystalline state. TEM observations showed Ca-α SiAlON hollow spheres composed of a large number of nanosized particles in the products prepared at 1450 °C for 120 min in nitrogen. In all systems, the Ca-α SiAlON hollow spheres were always produced through an intermediate Si–Al–Ca–O liquid phase in the same mechanism, regardless of the characteristics of SiO 2 starting powders used. Spherical solid particles consisted of amorphous phase containing Si, Al, Ca, O and a small amount of N were generated at the initial stage of carbothermal reduction–nitridation. These spherical solid particles changed into hollow particles with the progression of the reaction from the liquid phase to the crystalline Ca-α SiAlON with increasing temperature.
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Development of Advanced Ceramics by Powder Composite Process
Tatami Junichi, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi
KONA POWDER AND PARTICLE JOURNAL ( 28 ) 227 - 240 2010 [Reviewed]
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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INADA Makoto, TATAMI Junichi, MARUO Shoji
The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Japan Society of Mechanical Engineers Joint Work
A three-dimensional (3D) molding process based on two-photon microstereolithography and floc casting was proposed and developed to fabricate 3D ceramic microstructures. In this method, a 3D polymeric mold fabricated by two-photon microstereolithography is covered with ceramic slurry and then thermally decomposed to obtain real 3D ceramic microstructures. In this study, a highly concentrated slurry containing submicron fused Si02 particles was used to fabricate transparent Si02 glass microstructures. Thermal decomposition of a photopolymer was examined by thermogravimetry and differential thermal analysis (TG-DTA). The temperature profile of the heating process is optimized using the master decomposition curve (MDC) theory to reduce the number of harmful cracks during thermal decomposition. It was demonstrated that a transparent fullerene-like model and spiral model could be fabricated by the optimized thermal decomposition.
Other Link： https://ci.nii.ac.jp/naid/110008741842
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TATAMI Junichi, YOSHIO Sara, YAMAKAWA Tomohiro, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi
The Proceedings of the Materials and processing conference 2010 ( 0 ) _107-1_ - _107-3_ 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Japan Society of Mechanical Engineers Joint Work
CNT dispersed Si_3N4_ ceramics with double percolation structure were prepared by using granules of Si_3N_4 powder with and without CNTs followed by densification through spark plasma sintering process. Although the single percolation sample having 0.5wt% CNT was insulator because it was below percolation threshold, the electrical conductivity was showen in the double percolation sample having 0.5wt%. Consequently, it was shown that the electrical conductivity of CNT dispersed Si_3N_4 was able to be controlled by double percolation.
Other Link： https://ci.nii.ac.jp/naid/110008742940
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PREPARATION OF ZnO/Al2O3 NANOCOMPOSITE PARTICLES BY MECHANICAL TREATMENT
Tasaki Satoko, Tatami Junichi, Nakan Hiromi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS III 219 151 - + 2010
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Ohnishi Masahiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006977536
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Hashimoto Atsushi, Tatami Junichi, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006977551
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Fabrication of TiN particles dispersed Si3N4 ceramics by SPS
yamakawa tomohiro, tatami junichi, komeya katsutoshi, wakihara toru, hattori tomoya, Tu Ryo, goto t … Show more authors
yamakawa tomohiro, tatami junichi, komeya katsutoshi, wakihara toru, hattori tomoya, Tu Ryo, goto takashi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006977532
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Tatami Junichi, Nemoto Yuta, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Sugai Atsushi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978327
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Uemura Masaaki, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Sugai Athushi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978325
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Preparation of nano-zeolite by beads milling
Ichikawa Ryuma, wakihara toru, tatami junichi, komeya katsutoshi, meguro takeshi, gopinathan sankar … Show more authors
Ichikawa Ryuma, wakihara toru, tatami junichi, komeya katsutoshi, meguro takeshi, gopinathan sankar, kohara shinji Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 3I20 - 3I20 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979396
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Double percolation control electric resistive of CNT dispersed Si<SUB>3</SUB>N<SUB>4</SUB> ceramics
Yoshio Sara, Tatami Junichi, Wakihara Toru, Yamakawa Tomohiro, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006977537
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Evaluation of microscopically electrical property of Al-doped ZnO by SNDM
tasaki satoko, tatami junichi, wakihara toru, komeya katsutoshi, meguro takeshi, nakano hiromi, hoj … Show more authors
tasaki satoko, tatami junichi, wakihara toru, komeya katsutoshi, meguro takeshi, nakano hiromi, hojo junichi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2010 ( 0 ) 2010
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978309
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Development of advanced ceramics by powder composite process
Tatami, J. and Nakano, H. and Wakihara, T. and Komeya, K.
KONA Powder and Particle Journal 28 227 - 240 2010 [Reviewed]
Authorship：Lead author, Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Preparation of ZnO/Al<inf>2</inf>O<inf>3</inf> nanocomposite particles by mechanical treatment
Tasaki, S. and Tatami, J. and Nakano, H. and Wakihara, T. and Komeya, K. and Meguro, T.
Ceramic Transactions 219 151 - 154 2010
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Fabrication of ZnO ceramics using ZnO/Al2O3 nanocomposite particles prepared by mechanical treatment
Tasaki, Satoko and Tatami, Junichi and Nakano, Hiromi and Wakihara, Toru and Komeya, Katsutoshi … Show more authors
Tasaki, Satoko and Tatami, Junichi and Nakano, Hiromi and Wakihara, Toru and Komeya, Katsutoshi and Meguro, Takeshi Hide authors
Journal of the Ceramic Society of Japan 118 ( 1374 ) 118 - 121 2010 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Effects of starting composition and carbon content on the formation of Ca-alpha SiAION powders by carbothermal reduction-nitridation
Hotta, Mikinori and Tatami, Junichi and Komeya, Katsutoshi and Meguro, Takeshi and Cheng, Yi-Bi … Show more authors
Hotta, Mikinori and Tatami, Junichi and Komeya, Katsutoshi and Meguro, Takeshi and Cheng, Yi-Bing Hide authors
Journal of the Ceramic Society of Japan 118 ( 1381 ) 827 - 829 2010 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Yokoyama Takashi, Meguro Takeshi, Nakamura Masaru, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi
JOURNAL OF CERAMIC PROCESSING RESEARCH 10 ( 5 ) 683 - 688 2009.10 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Influence of coarse particles on microstructure of aluminum nitride sintered body
Kuibira Akira, Okada Hiroshi, Nakata Hirohiko, Kawaguchi Hirotatsu, Tatami Junichi, Wakihara Toru, … Show more authors
Kuibira Akira, Okada Hiroshi, Nakata Hirohiko, Kawaguchi Hirotatsu, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi Hide authors
ADVANCED POWDER TECHNOLOGY 20 ( 5 ) 464 - 467 2009.9 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Aluminum nitride (AlN) is used for quick diffusion and elimination of heat that is generated from electronic devices, such as power modules used for hybrid cars and micro processing units (MPUs) of computers. AlN provides high thermal conductivity, and it is known that its sintering performance and sintered body characteristics vary with the quality of AlN raw powder. When two types of commercially available AlN raw powder produced by the same reductive nitriding method were compared, the sintering performance and the thermal conductivity of sintered compacts processed from low-price AlN material powder were found to be lower than those of sintered compacts processed from high-price, high-purity, evenly granulated, and fine AlN material powder. As one of the causes of the foregoing, the effect of coarse particles contained in AlN material powder was investigated. The investigation results indicated that the coarse particles were AlN and the powder with the coarse particles removed by sifting out with sieves provided sintering performance and sintering behavior similar to those of high-price and high-purity AlN material powder. It was therefore found that the coarse particle constituted a sintering inhibiting factor. This paper reports the investigation results.
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Fabrication of three-dimensional transparent SiO2 microstructures by microstereolithographic molding
Makoto Inada, Daisuke Hiratsuka, Junichi Tatami
Japanese journal of applied physics : JJAP 48 ( 6 ) 2009.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics Joint Work
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Inada, M; Hiratsuka, D; Tatami, J; Maruo, S
JAPANESE JOURNAL OF APPLIED PHYSICS 48 ( 6 ) 06FK01 2009.6
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：IOP Publishing Joint Work
A three-dimensional (3D) molding process based on microstereolithography and floc casting was proposed and developed to fabricate 3D ceramic microstructures. In this method, a 3D polymeric mold fabricated by microstereolithography is covered with ceramic slurry and then thermally decomposed to obtain real 3D ceramic microstructures. In this study, a highly concentrated slurry (60.9 vol %) containing submicron fused SiO2 particles was used to fabricate transparent SiO2 glass microstructures. Thermal decomposition of a photopolymer was examined by thermogravimetry and differential thermal analysis (TG–DTA). The temperature profile of the heating process is optimized using the master decomposition curve (MDC) theory to reduce the number of harmful cracks during thermal decomposition. It was demonstrated that a transparent fullerene-like model could be fabricated by the optimized thermal decomposition.
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Yamakawa, T; Wakihara, T; Tatami, J; Komeya, K; Meguro, T
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 117 ( 1364 ) 542 - 542 2009.4 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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A New Method for the Synthesis of Alumina Nanotubes from Polymer Composite Materials
Wakihara Toru, Hirasaki Tetsuro, Shinoda Masashi, Meguro Takeshi, Tatami Junichi, Komeya Katsutoshi … Show more authors
Wakihara Toru, Hirasaki Tetsuro, Shinoda Masashi, Meguro Takeshi, Tatami Junichi, Komeya Katsutoshi, Inagaki Satoshi, Kubota Yoshihiro Hide authors
CRYSTAL GROWTH & DESIGN 9 ( 3 ) 1260 - 1263 2009.3 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work
A new approach for the synthesis of Al2O3 nanotube has been performed by the calcination of polymer composite materials fabricated via the simultaneous curing of furfuryl alcohol and the polymerization of aluminum isopropoxide. At first, mixture of furfuryl alcohol and aluminum isopropoxide was prepared and heated at 90 °C for 240 h. During this process, furfuryl alcohol is cured to release H2O, and the polymerization of aluminum isopropoxide is promoted gradually by the generated H2O. Al2O3 nanotube was obtained by the calcination of the polymer composite materials at 1300 °C in argon for 2 h followed by the carbon elimination at 700 °C for 120 min in atmospheric conditions. The nanotubes are typically about 1−2 μm in length; the outer diameter and wall thickness are about 30−70, and 10 nm, respectively, for most of the nanotubes.
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Mechanical properties of alpha- and beta-SiAlON composite ceramics using beta-SiAlON powder
Asakoshi Kei, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Yokouchi Masahiro
SIAIONS AND NON-OXIDES 403 111 - + 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>β-SiAlON powder was used as a raw powder to fabricate α/β-SiAlON composite ceramics with different rare earth elements. The phases present in the sample fabricated from -SiAlON, α-Si3N4, AlN, and rare earth oxide powders were - and -SiAlONs. The composition was dependent on the chemical composition and firing profile. The sample obtained by adding Yb2O3 had a high -SiAlON content. The /-SiAlON composite ceramics had high densit. Their microstructures depended on the used metal oxides, namely, the addition of Nd2O3 and CaCO3 resulted in the elongation of the -SiAlON grains. The bending strength, fracture toughness, and hardness were influenced by the -SiAlON content, amount of elongated grains, and density of the sample.</jats:p>
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High-Temperature Compressive Deformation of SiAlON Polycrystals Prepared without Additives
Chihara Kentarou, Hiratsuka Daisuke, Tatami Junichi, Wakai Fumihiro, Komeya Katsutoshi
SIAIONS AND NON-OXIDES 403 117 - + 2009
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Matsuoka Mitsuaki, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Take … Show more authors
Matsuoka Mitsuaki, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 327 - 327 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979640
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Fabrication of electrically conductive Si(3)N(4) ceramics by dispersion of carbon nanotubes
Yoshio Sara, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
SIAIONS AND NON-OXIDES 403 19 - 22 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Electrically conductive Si3N4 ceramics were fabricated by dispersion of different characteristics of carbon nanotubes (CNTs). When the sintering aid of Y2O3-Al2O3-TiO2-AlN was used for lower temperature densification, it was confirmed that CNTs existed in Si3N4 ceramics from SEM observation and SiC was not identified in XRD analysis, which means that CNTs did not react with Si3N4. Relative density and electrical conductivity of the CNT dispersed Si3N4 ceramics depended on the characteristics of CNTs. Aggregation of CNTs, which is outstanding in much thinner CNTs, should limit densification of Si3N4. CNTs were well-dispersed by beads milling in ethanol. As a result, beads milling process was confirmed to be effective in unraveling and dispersing CNTs. It was shown that better dispersion of CNTs with higher aspect ratio resulted in higher density and electrical conductivity.</jats:p>
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Hiratsuka Daisuke, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
SIAIONS AND NON-OXIDES 403 245 - 248 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>AlN ceramics used in electronic substrates and packages are fabricated by the densification of green bodies with sintering aids such as rare-earth oxides. The homogeneous dispersion of the sintering aids, achieved with the help of the mechanochemical bonding of several types of fine powders, is the key process for obtaining a good sinterability and high performance. In this study, we fabricated the AlN ceramics using AlN and nano-Y2O3 composite particles prepared by mechanical treatment. The AlN powder and nano-Y2O3 powder were ball-milled with Al2O3 balls and a dispersant in ethanol in a plastic pot. The powder mixture of AlN and Y2O3 was composited by mechanical treatment. The composite powder was granulated and pressed to obtain a green body. After dewaxing, the AlN green body was fired at 1800°C in 0.6 MPa N2. The sintered body possessed a fracture toughness of 3.6 Pa•m1/2, higher than that, 3.1 Pa•m1/2, of the AlN ceramics fabricated without the mechanical treatment. An observation of the fractured surface revealed that grain boundary reinforcement enhances the fracture toughness of the AlN ceramics made of composite particles.</jats:p>
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Fabrication and evaluation of AlN-SiC solid solutions with p-type electrical conduction
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Ta … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Takashi Hide authors
SIAIONS AND NON-OXIDES 403 39 - + 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>AlN–SiC solid solutions with p-type electrical conduction were fabricated with the addition of small amounts of Al and C. Powder mixtures of AlN and SiC with small amounts of Al and C (below 10 mol%) were consolidated by spark plasma sintering (SPS) at 2000°C for 10 min under 1 atm Ar, and then heat-treated at 2200°C for 3 h in an Ar flow to afford 2H AlN–SiC solid solutions. The relative densities of the 50AlN-50SiC-Al4C3 (A50-1AC) and 50AlN-50SiC-3Al4C3 (A50-3AC) samples were about 95%, whereas that of the 75AlN-25SiC-Al4C3 (A75-1AC) sample was about 86%. X-ray diffractometry (XRD) analysis showed that the samples comprised only the 2H phase, and except in the case of the A50-3AC sample, no diffraction peaks of Al and C were observed. Although the samples without the additives (Al and C) were electrical insulators, addition of Al and C introduced p-type semiconduction. The electrical conductivities at 300°C of the A50-1AC and A50-3AC samples were about 30 and 100 S/m, respectively, whereas that of the A75-1AC sample was about 10–1 S/m. It was found that addition of Al and C brought about electrical conduction in AlN–SiC solid solutions.</jats:p>
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Pressure assisted sinter-joining of AlN ceramics
Kubota Kenichi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976457
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Kodama Eriko, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi, Nakano Hiromi
SIAIONS AND NON-OXIDES 403 221 - + 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>TiN nanoparticle-dispersed Si3N4 ceramics is one of the typical ceramics used for bearing applications. Because larger TiN particles considerably damage the mating metallic materials, smaller TiN particles must be dispersed in Si3N4 ceramics. In this study, we fabricated TiN nanoparticle-dispersed Si3N4 ceramics from Si3N4–nano TiO2 composite particles prepared by mechanical treatment. The mechanical properties of the fabricated TiN nanoparticle-dispersed Si3N4 ceramics were evaluated. At first, TiO2 nanoparticles were dispersed in ethanol using polyethylene imide as a dispersant with a lower molecular weight. Si3N4 powder was mixed with this slurry to obtain a powder mixture. In this case, the reaggregation of the TiO2 nanoparticles during the drying process is the problem that has to be solved. In this study, TiO2 nanoparticles and Si3N4 particles were mechanically joined by a particle composer to fabricate the composite particles from the powder mixture. TiN nanoparticles were uniformly dispersed in Si3N4 ceramics by using composite powder. The bending strength of the developed Si3N4 ceramics with TiN nanoparticles was improved, and its distribution was narrow due to the homogeneous dispersion of TiN nanoparticles.</jats:p>
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Effect of HfO2 and TiO2 addition on sintering behavior of silicon nitride ceramics.
Yamakawa Tomohiro, Komeya katsutoshi, Tatami Junichi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978723
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Observation of fracture behavior of PZT ceramics by scanning probe microscope
Matsunaga Akihiro, Nakada Satoshi, Tasaki Satoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, … Show more authors
Matsunaga Akihiro, Nakada Satoshi, Tasaki Satoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 349 - 349 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979407
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Observation of Fracture Surface of PMN-PT Single Crystal by Scanning Probe Microscopy
Matsunaga Akihiro, Tasaki Satoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976809
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Hybrid nanofractography of BaTiO<sub>3</sub> single crystal by scanning probe microscopy
Tatami Junichi, Nakada Satoshi, Tasaki Satoko, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 552 - 552 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979563
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Xin Ping, Ando Masahiro, Kawakami Shunichi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Megor … Show more authors
Xin Ping, Ando Masahiro, Kawakami Shunichi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Megoro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 3E09 - 3E09 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976547
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Kawakami Shunichi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Xin Ping, Ando … Show more authors
Kawakami Shunichi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Xin Ping, Ando Masahiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 3E08 - 3E08 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976549
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tanzawa takahiro, tatami junichi, wakihara toru, komeya katsutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 321 - 321 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979654
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Kunishima Takeshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975958
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Tasaki Satoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Nakano Hiromi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 484 - 484 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976322
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Tatami Junichi, Miyazaki Shinji, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Nakano Hiromi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978287
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Electrical resistivity of AlN ceramics without additive
Ohguni Hideyuki, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976468
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Suzuki Svetlana, Meguro Takeshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Yamashita Tsugito
Proceedings of JIEP Annual Meeting 23 ( 0 ) 260 - 261 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Japan Institute of Electronics Packaging Joint Work
Other Link： https://ci.nii.ac.jp/naid/130005469432
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Evaluation of composite ratio of Si3N4-TiO2 nano composite particles by zeta potential measurment
Noguchi Makoto, Tatami Jyunichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Nakano Hiromi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976464
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Synthesis of Ba containing sialon S-phase from a Zeolite by Reduction Nitridation Method
Ihara Akio, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976533
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Analysis of dispersion behavior of carbon nanotubes in liquid
Yoshio Sara, Tatami Junichi, Yamakawa Tomohiro, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, A … Show more authors
Yoshio Sara, Tatami Junichi, Yamakawa Tomohiro, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Aramaki Kenji Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 328 - 328 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979638
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Hagimura Sayaka, Tatami Jyunichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 56 - 56 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979576
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Wakihara Toru, Saito Yuri, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Fukuda Yumi, Matsuda … Show more authors
Wakihara Toru, Saito Yuri, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Fukuda Yumi, Matsuda Naotoshi, Asai Hironori Hide authors
SIAIONS AND NON-OXIDES 403 141 - + 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Rare-earth activated oxynitride or nitride luminescent materials have attracted considerable attention due to their potential applications as phosphors and pigments. Eu2+-doped -sialon has been reported to represent a new class of green phosphors with high efficiency. In this study, -sialon phosphor was synthesized by reduction nitridation of a zeolite. Eu ion-exchanged zeolite was fired at 1400 °C for 1 hour under NH3 gas containing 0.5 vol%C3H8. As a result, formation of -sialon with green emission under UV irradiation was confirmed. </jats:p>
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Sintering shrinkage behavior of Si3N4 ceramics prepared by a post-reaction sintering technique
Yabuki Hiromasa, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kita Hideki, Kon … Show more authors
Yabuki Hiromasa, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kita Hideki, Kondo Naoki, Hirao Kiyoshi Hide authors
SIAIONS AND NON-OXIDES 403 31 - + 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Post-reaction sintering is one of the fabrication processes of Si3N4 ceramics, which has received considerable attention as a cost-effective process due to the use inexpensive Si powder as a raw material. So far, many researches on the development of this method have been performed in order to improve their properties; however, the sintering shrinkage behavior, which is valuable for the optimization of the firing conditions, has not been well clarified. In this study, we focus on the post-reaction sintering of the Si-Y2O3-Al2O3 system, and investigate its sintering shrinkage behavior by dilatometery. It was found that there is no shrinkage from 1400 to 1600 °C due to grain rearrangements in the green body of the reaction-bonded Si3N4. Furthermore, the shrinkage of the reaction-bonded Si3N4 commenced at approximately 1750 °C, which is higher than the shrinkage temperature of the green body of conventional Si3N4 powder. The restriction of the shrinkage appears to result from the neck growth and strong aggregation among the reacted Si3N4 particles.</jats:p>
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Sintering shrinkage behavior and mechanical properties of HfO(2)-added Si(3)N(4) ceramics
Horikawa Daisuke, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
SIAIONS AND NON-OXIDES 403 35 - 38 2009
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>HfO2-added Si3N4 ceramics are known to exhibit excellent high-temperature strength and excellent damage characteristics because HfO2 assists the crystallization of the grain boundary phase. However, the sintering shrinkage behavior and mechanical properties of HfO2-added Si3N4 have not been well clarified so far, although it has been reported that TiO2, in which Ti is from the same group as Hf in the periodic table, enhances the densification of the Si3N4-Y2O3-Al2O3-AlN system and wear resistance due to TiN formed from TiO2 and AlN in the grain boundary. In the present study, we focus on HfO2 as the sintering aid to investigate the sintering shrinkage behavior and mechanical properties of HfO2-added Si3N4. The powder mixtures are prepared by the addition of HfO2 to the Si3N4-Y2O3-Al2O3 or Si3N4-Y2O3-Al2O3-AlN system. The sintering shrinkage curves of HfO2-added Si3N4 ceramics show rapid shrinkage at 1600°C as compared with those of the Si3N4 ceramics without HfO2.The shrinkage can be explained by the formation of SiO2-Y2O3-HfO2 derived liquid phases. Furthermore, the mechanical properties of HfO2-added Si3N4 were as excellent as those of the Si3N4 ceramics without HfO2.</jats:p>
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Tanzawa Takahiro, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takes … Show more authors
Tanzawa Takahiro, Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976466
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Hagimura Sayaka, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Nishimura Toshiy … Show more authors
Hagimura Sayaka, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Nishimura Toshiyuki Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2009 ( 0 ) 2009
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975302
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Wakihara, T. and Saito, Y. and Tatami, J. and Komeya, K. and Meguro, T. and Fukuda, Y. and Matsuda, … Show more authors
Wakihara, T. and Saito, Y. and Tatami, J. and Komeya, K. and Meguro, T. and Fukuda, Y. and Matsuda, N. and Asai, H. Hide authors
Key Engineering Materials 403 141 - 144 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications Ltd. Joint Work
<jats:p>Rare-earth activated oxynitride or nitride luminescent materials have attracted considerable attention due to their potential applications as phosphors and pigments. Eu2+-doped -sialon has been reported to represent a new class of green phosphors with high efficiency. In this study, -sialon phosphor was synthesized by reduction nitridation of a zeolite. Eu ion-exchanged zeolite was fired at 1400 °C for 1 hour under NH3 gas containing 0.5 vol%C3H8. As a result, formation of -sialon with green emission under UV irradiation was confirmed. </jats:p>
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Yabuki, H. and Wakihara, T. and Tatami, J. and Komeya, K. and Meguro, T. and Kita, H. and Kondo, N. … Show more authors
Yabuki, H. and Wakihara, T. and Tatami, J. and Komeya, K. and Meguro, T. and Kita, H. and Kondo, N. and Hirao, K. Hide authors
Key Engineering Materials 403 31 - 34 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Horikawa, D. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Key Engineering Materials 403 35 - 38 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications Ltd. Joint Work
<jats:p>HfO2-added Si3N4 ceramics are known to exhibit excellent high-temperature strength and excellent damage characteristics because HfO2 assists the crystallization of the grain boundary phase. However, the sintering shrinkage behavior and mechanical properties of HfO2-added Si3N4 have not been well clarified so far, although it has been reported that TiO2, in which Ti is from the same group as Hf in the periodic table, enhances the densification of the Si3N4-Y2O3-Al2O3-AlN system and wear resistance due to TiN formed from TiO2 and AlN in the grain boundary. In the present study, we focus on HfO2 as the sintering aid to investigate the sintering shrinkage behavior and mechanical properties of HfO2-added Si3N4. The powder mixtures are prepared by the addition of HfO2 to the Si3N4-Y2O3-Al2O3 or Si3N4-Y2O3-Al2O3-AlN system. The sintering shrinkage curves of HfO2-added Si3N4 ceramics show rapid shrinkage at 1600°C as compared with those of the Si3N4 ceramics without HfO2.The shrinkage can be explained by the formation of SiO2-Y2O3-HfO2 derived liquid phases. Furthermore, the mechanical properties of HfO2-added Si3N4 were as excellent as those of the Si3N4 ceramics without HfO2.</jats:p>
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Mechanical properties of α- and β-SiAlON composite ceramics using β-SiAlON powder
Asakoshi, K. and Tatami, J. and Komeya, K. and Meguro, T. and Yokouchi, M.
Key Engineering Materials 403 111 - 114 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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High-temperature compressive deformation of SiAION polycrystals prepared without additives
Chinara, K. and Hiratsuka, D. and Tatami, J. and Wakai, F. and Komeya, K.
Key Engineering Materials 403 117 - 120 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Yoshio, S. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Key Engineering Materials 403 19 - 22 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Hiratsuka, D. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Key Engineering Materials 403 245 - 248 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Kodama, E. and Tatami, J. and Wakihara, T. and Meguro, T. and Komeya, K. and Nakano, H.
Key Engineering Materials 403 221 - 224 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of AlN-SiC solid solutions with p-type electrical conduction
Kobayashi, R. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T. and Tu, R. and Goto, T.
Key Engineering Materials 403 39 - 42 2009
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications Ltd. Joint Work
<jats:p>AlN–SiC solid solutions with p-type electrical conduction were fabricated with the addition of small amounts of Al and C. Powder mixtures of AlN and SiC with small amounts of Al and C (below 10 mol%) were consolidated by spark plasma sintering (SPS) at 2000°C for 10 min under 1 atm Ar, and then heat-treated at 2200°C for 3 h in an Ar flow to afford 2H AlN–SiC solid solutions. The relative densities of the 50AlN-50SiC-Al4C3 (A50-1AC) and 50AlN-50SiC-3Al4C3 (A50-3AC) samples were about 95%, whereas that of the 75AlN-25SiC-Al4C3 (A75-1AC) sample was about 86%. X-ray diffractometry (XRD) analysis showed that the samples comprised only the 2H phase, and except in the case of the A50-3AC sample, no diffraction peaks of Al and C were observed. Although the samples without the additives (Al and C) were electrical insulators, addition of Al and C introduced p-type semiconduction. The electrical conductivities at 300°C of the A50-1AC and A50-3AC samples were about 30 and 100 S/m, respectively, whereas that of the A75-1AC sample was about 10–1 S/m. It was found that addition of Al and C brought about electrical conduction in AlN–SiC solid solutions.</jats:p>
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TATAMI Junichi
Ceramics Japan 43 ( 10 ) 840 - 844 2008.10
Language：English Publishing type：Research paper (scientific journal) Single Work
Other Link： https://ci.nii.ac.jp/naid/10024784066
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In Situ Measurement of Shrinkage During Postreaction Sintering of Reaction-Bonded Silicon Nitride
Wakihara Toru, Yabuki Hiromasa, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Hyuga Hideki, Ki … Show more authors
Wakihara Toru, Yabuki Hiromasa, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Hyuga Hideki, Kita Hideki Hide authors
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 91 ( 10 ) 3413 - 3415 2008.10 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>The reaction‐bonding technique is one of the major fabrication processes of silicon nitride (Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub>) ceramics, which has received much attention as a cost‐effective process due to the use of cheap Si powder as a raw material. Many studies on the development of this method have been performed in order to improve their properties; however, the sintering shrinkage behavior, which is a very important information to optimize the firing condition, has not been well clarified. In this study, we focused on the reaction‐bonding technique of the Si–Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> system. At first, reaction‐bonded body of the Si–Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> system was prepared, and then its postreaction sintering shrinkage behavior was investigated by <jats:italic>in situ</jats:italic> dilatometry. It was found that no shrinkage occurred from 1400° to 1600°C due to grain rearrangement in the reaction‐bonded Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> body. Furthermore, the shrinkage of the reaction‐bonded Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> started around 1750°C, which is a higher temperature compared with the green body of conventional Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> powder. The restriction of shrinkage seems to result from neck growth and strong aggregation among reacted Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> particles.</jats:bold> </jats:p>
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NMR study on the formation mechanism of β-SiAlON from zeolite by nitridation using ammonia gas
116 ( 1357 ) 980 - 983 2008.9 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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HIRASAKI Tetsuro, MEGURO Takeshi, WAKIHARA Toru, TATAMI Junichi, KOMEYA Katsutoshi
Tanso ( 233 ) 181 - 186 2008.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10021128002
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Fabrication and wear properties of TiN nanoparticle-dispersed Si3N4 ceramics
Tatami Junichi, Kodama Eriko, Watanabe Hiroshi, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi, Me … Show more authors
Tatami Junichi, Kodama Eriko, Watanabe Hiroshi, Nakano Hiromi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Azushima Akira Hide authors
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 116 ( 1354 ) 749 - 754 2008.6 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
TiN particle-dispersed Si<sub>3</sub>N<sub>4</sub> ceramics are applied to bearing materials because of their excellent mechanical and thermal properties, chemical stability, etc. In particular, hybrid bearings composed of Si<sub>3</sub>N<sub>4</sub> ceramics and metals are more popular because of low production costs. In such hybrid bearings, control of abrasive wear of metals by hard TiN particles is required. The objective of this study is development of TiN nanoparticle-dispersed Si<sub>3</sub>N<sub>4</sub> ceramics that cause low damage to the mating metals. In order to disperse TiN nanoparticles in Si<sub>3</sub>N<sub>4</sub> ceramics, TiO<sub>2</sub> nanoparticles and Si<sub>3</sub>N<sub>4</sub> particles were mixed by mechanical treatment. TEM observation showed that TiO<sub>2</sub> nanoparticles were directly bonded to submicron Si<sub>3</sub>N<sub>4</sub> particles. Si <sub>3</sub>N<sub>4</sub> ceramics in which TiN nanoparticles were uniformly dispersed were fabricated using the composite particles. The amount of damage caused by the Si<sub>3</sub>N<sub>4</sub> ceramics with TiN nanoparticles, developed in this study, to the mating metals in ball-on-disk test is comparable to damage caused by the Si<sub>3</sub>N<sub>4</sub> ceramics without TiN particles.
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Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Goto Takashi, Tu … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Goto Takashi, Tu Rong Hide authors
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 91 ( 5 ) 1548 - 1552 2008.5 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>Dense aluminum nitride–silicon carbide (AlN–SiC) solid solutions with a 2H structure were fabricated by the post‐heat treatment of dense AlN–SiC composites fabricated by spark plasma sintering (SPS). The changes in the relative density, microstructure, and phases present were investigated for the compositions of 25 mol% AlN–75 mol% SiC (AlN 25), 50 mol% AlN–50 mol% SiC (AlN 50), and 75 mol% AlN–25 mol% SiC (AlN 75). The AlN–SiC composites fabricated by the SPS were dense ceramics with fine microstructures and composed of 2H and 6H AlN–SiC solid solutions. The AlN 50 samples heat treated at 2200°C and the AlN 75 samples heat treated at 2100°C were also dense ceramics and composed of only the 2H AlN–SiC solid solution. In contrast, the AlN 25 samples heat treated at 2200°C were porous ceramics and composed of several AlN–SiC solid solutions (2H, 4H, 6H, and 15R), and the AlN 75 samples heat treated at 2200°C were decomposed into an Al melt. Dense AlN–SiC solid solutions composed of only the 2H phase can be obtained by controlling the heat‐treatment temperatures, except for the AlN 25 sample.</jats:bold> </jats:p>
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Hotta Mikinori, Tatami Junichi, Komeya Katsutoshi, Zhang Cheng, Meguro Takeshi, Terner Mark R., Che … Show more authors
Hotta Mikinori, Tatami Junichi, Komeya Katsutoshi, Zhang Cheng, Meguro Takeshi, Terner Mark R., Cheng Yi-Bing Hide authors
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 91 ( 3 ) 860 - 864 2008.3 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>Carbothermal reduction–nitridation (CRN) of SiO<jats:sub>2</jats:sub>–Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–CaO powders was performed under various firing conditions to investigate the formation process of Ca‐α sialon hollow balls composed of nanosized particles. Scanning electron microscopy and transmission electron microscopy observations of the samples obtained at different firing temperatures confirmed that solid spherical particles were formed at the early stage of the reaction, and nanosized particles were subsequently produced on the surface of these solid balls. From X‐ray diffraction and energy‐dispersive spectrometry analyses, it was found that the solid balls initially formed at 1450°C were mainly amorphous and contained Si, Al, Ca, O, and a small amount of N. Further nitridation at 1450°C gradually converted the solid balls into Ca‐α sialon hollow balls over time. The results revealed that the formation of Ca‐α sialon hollow balls depends on the formation of solid balls from the Si–Al–Ca–O liquid phase at the initial stage of the CRN process.</jats:bold> </jats:p>
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Chihara Kentarou, Hiratsuka Daisuke, Shinoda Yutaka, Akatsu Takashi, Wakai Fumihiro, Tatami Junichi … Show more authors
Chihara Kentarou, Hiratsuka Daisuke, Shinoda Yutaka, Akatsu Takashi, Wakai Fumihiro, Tatami Junichi, Komeya Katsutoshi Hide authors
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS 148 ( 1-3 ) 203 - 206 2008.2
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Electric Double Layer Capacitor Characteristics of Carbon Blacks Activated by Potassium Hydroxide
Amaoka Toshikazu, Meguro Takeshi, Yamashita Tsugito, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutos … Show more authors
Amaoka Toshikazu, Meguro Takeshi, Yamashita Tsugito, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi Hide authors
材料の科学と工学 = Materials science and technology 45 ( 1 ) 19 - 23 2008.2 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：日本材料科学会 Joint Work
Other Link： https://ci.nii.ac.jp/naid/10024353011
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Synthesis of .BETA.-SiAlON from a zeolite by reduction nitridation in a mixture of NH3-C3H8
116 ( 1350 ) 325 - 328 2008.2 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Katou Keita, Yokoyama Takashi, Meguro Takeshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 3B02 - 3B02 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006976211
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Tatami Junichi, Takahashi Kenji, Yoshio Sara, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978477
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Sintering behavior of HfO<SUB>2</SUB> and TiO<SUB>2</SUB> added Si<SUB>3</SUB>N<SUB>4</SUB> ceramics
Horikawa Daisuke, Komeya Katsutoshi, Tatami Junichi, Wakihara Toru, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978474
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Fabrication of CNT dispersed Si3N4 ceramics by HfO and addition
yamakawa tomohiro, Tatami junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 476 - 476 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974617
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ELECTRICAL PROPERTIES OF AIN-SiC SOLID SOLUTIONS WITH ADDITIONS OF Al AND C
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
MECHANICAL PROPERTIES AND PERFORMANCE OF ENGINEERING CERAMICS AND COMPOSITES III 28 ( 2 ) 111 - 115 2008
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Yosho Sara, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978476
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Observation of fracture behavior of BaTiO<SUB>3</SUB> by scanning probe microscope
Nakada Satoshi, Tasaki Satoko, Tatami Junichi, Wakihara toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 121 - 121 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972258
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Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Goto Takashi, Tu … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Goto Takashi, Tu Rong Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 3B19 - 3B19 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975927
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HIRATSUKA Daisuke, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006977952
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INADA Makoto, HIRATSUKA Daisuke, TATAMI Junichi, MARUO Shoji
The proceedings of the JSME annual meeting 2008 ( 0 ) 223 - 224 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Japan Society of Mechanical Engineers Joint Work
Three-dimensional (3-D) molding processes based on microstereolithography was proposed and developed. To make 3-D ceramic microstructures, a 3-D mold made from a photopolymer, which is covered with ceramic slurry, is thermally decomposed. In our method, high concentration slurry (67.9vol.%) containing submicron SiO_2 particles is used for making high-density (99.7%) SiO_2 Glass. Pyrolysis process of the photopolymer was examined by TG-DTA measurement. The heating condition is optimized by using master decomposition curve theory. The optimal pyrolysis process made it possible to make 3-D ceramic microstructures such as a rotor model and a fullerene model. The further optimization of the pyrolysis process is needed for making crack-free ceramic 3-D microstructures with high fidelity.
Other Link： https://ci.nii.ac.jp/naid/110007658980
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INADA Makoto, HIRATSUKA Daisuke, TATAMI Junichi, MARUO Shoji
The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) 2008 ( 0 ) _2A1-F05_1 - _2A1-F05_3 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Japan Society of Mechanical Engineers Joint Work
Three-dimensional (3-D) molding processes based on microstereolithography was proposed and developed. To make 3-D ceramic microstructures, a 3-D mold made from a photopolymer, which is covered with ceramic slurry, is thermally decomposed. In our method, high concentration slurry (67.9vol.%) containing submicron SiO2 particles is used for making high-density (99.7%) SiO_2 Glass. Pyrolysis process of the photopolymer was examined by TG-DTA measurement. The heating condition is optimized by using master decomposition curve theory. The optimal pyrolysis process made it possible to make 3-D ceramic microstructures such as a rotor model and a fullerene model. The further optimization of the pyrolysis process is needed for making crack-free ceramic 3-D microstructures with high fidelity.
Other Link： https://ci.nii.ac.jp/naid/110008696327
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1453 Mechanical Properties of CNT dispersed Si_3N_4 ceramics
TATAMI Junichi, YOSHIO Sara, TAKAHASHI Kenji, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi, AZU … Show more authors
TATAMI Junichi, YOSHIO Sara, TAKAHASHI Kenji, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi, AZUSHIMA Akira Hide authors
The proceedings of the JSME annual meeting 2008 ( 0 ) 313 - 314 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Japan Society of Mechanical Engineers Joint Work
CNT dispersed Si_3N_4 ceramics were fabricated by adding HfO_2 and TiO_2 to Si_3N_4Y_2O_3Al_2O_3-AIN system. As a result, dense sintered body was obtained; especially the relative density of the 5HOT sample was 98.7% after hot isostatic pressing process. It was found that a large amount of CNT existed in Si_3N_4 ceramics. Consequently, HfO_2 and TiO_2 addition was effective in fabrication of dense CNT dispersed Si_3N_4 ceramics at lower temperature.
Other Link： https://ci.nii.ac.jp/naid/110007658551
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Synthesis of SiC powder by carbothermal reduction of SiO<SUB>2</SUB>
Sakurai Kento, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979133
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Amorphization Mechanism of Zeolite Characterized by High-Energy X-ray Diffraction Technique
wakihara toru, Kohara Shinji, tatami junichi, meguro takeshi, komeya katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 499 - 499 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974708
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Synthesis of green-emitting Eu2+-doped Sr-SiAlON phosphors by gas reduction nitridation
ando tatsuya, wakihara toru, tatami junichi, komeya katsutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 614 - 614 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979170
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Crack propagation behavior observation of BaTiO3 ceramics by scanning probe microscope
nakada satoshi, tasaki satoko, tatami junichi, wakihara toru, komeya katsutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979789
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Kunishima Takeshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 138 - 138 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972224
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In-situ measurement of sintering shrinkage behavior of silicon carbide
Kawakami Shunichi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Xin Ping, Ando … Show more authors
Kawakami Shunichi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Xin Ping, Ando Masahiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 464 - 464 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974520
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AlN-nano Y<sub>2</sub>O<sub>3</sub> composite particles prepared by mechanical treatment
HIRATSUKA Daisuke, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi, NAKANO Hiromi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 139 - 139 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972225
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Tasaki Satoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Nakano Hiromi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 140 - 140 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972232
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Electrical properties of AlN-SiC solid solutions fabricated by spark plasma sintering
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Rong Tu, Goto Ta … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Rong Tu, Goto Takashi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 620 - 620 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979146
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Fabrication of SiO<SUB>2</SUB> sintered body using micro resin mold
Hiratsuka Daisuke, Inada Makoto, Maruo Shoji, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meg … Show more authors
Hiratsuka Daisuke, Inada Makoto, Maruo Shoji, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 618 - 618 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979147
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Tatami Junichi, Hashidume Kousuke, Hiratsuka Daisuke, Wakihara Toru, Komeya Katsutoshi, Meguro Take … Show more authors
Tatami Junichi, Hashidume Kousuke, Hiratsuka Daisuke, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 463 - 463 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974542
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Hirasaki Tetsuro, Meguro Takeshi, Wakihara Toru, Wakihara Toru, Tatami Junichi
TANSO 2008 ( 233 ) 181 - 186 2008 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：THE CARBON SOCIETY OF JAPAN Joint Work
The effect of ultrasonic irradiation for the polymerization of furfuryl alcohol (FA) with a pore-forming agent on the microstructure of the carbons derived from the furan resin was investigated. Tetra ethylene glycol (TEG) and ethylene glycol (EG) were examined as the pore-forming agents. In the system of FA-TEG, atendency for the surface area to increase with increasing power of ultrasonic wave was recognized. The irradiation under 400 W and 500 W gave the surface areas larger than 900 m<SUP>2</SUP>/g. The micropore volume and the surface area were the larges in the carbon derived from the furan resin made from the mixture with equivalent amounts of FA and TEG.<BR>A comparison of the numbers of ethyl group between TEG and EG showed that the morphology and the microstructure were significantly different. The effect of TEG in terms of pore development was confirmed to bemore effective than EG.
Other Link： https://ci.nii.ac.jp/naid/130004358744
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Dispersion of carbon nanotubes by beads milling and its application
Yoshio Sara, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Aramaki Kenji
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 151 - 151 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972208
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wakihara toru, yabuki hiromasa, tatami junichi, komeya katsutoshi, meguro takeshi, kondo naoki, hyu … Show more authors
wakihara toru, yabuki hiromasa, tatami junichi, komeya katsutoshi, meguro takeshi, kondo naoki, hyuga hideki, kita hideki Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006978471
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Fabrication Si3N4 ceramics using Y2O3-HfO2 Additives
HAGIMURA SAYAKA, TATAMI JYUNICHI, WAKIHARA TORU, KOMEYA KATSUTOSHI, MEGURO TAKESHI
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2008 ( 0 ) 619 - 619 2008
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006979149
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Electrical properties of AlN-SiC solid solutions with additions of Al and C
Kobayashi, R. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Ceramic Engineering and Science Proceedings 28 ( 2 ) 111 - 115 2008 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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粒子複合化プロセスによるナノ粒子分散型窒化ケイ素セラミックスの開発
多々見 純一, 渡邊 洋史, 脇原 徹
粉砕 = The micromeritics ( 51 ) 52 - 56 2008 [Reviewed]
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：枚方 : ホソカワミクロン Joint Work
コレクション : 国立国会図書館デジタルコレクション > 電子書籍・電子雑誌 > その他
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Progress of Non-Oxide Ceramics as Heat-Resistant Materials
KOMEYA Katsutoshi, TATAMI Junichi
Materials science and technology 44 ( 6 ) 249 - 253 2007.12 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10024352913
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粒子複合化プロセスによるナノ粒子分散型窒化ケイ素セラミックスの開発
多々見純一, 渡邊洋史, 脇原徹
粉砕 (51) 2007.11 [Reviewed]
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ホソカワミクロン Joint Work
収集根拠 : オンライン資料収集制度
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Glass-like carbon derived from a polymer consisting of furfuryl alcohol and tetraethylene glycol
Hirasaki Tetsuro, Meguro Takeshi, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi
JOURNAL OF MATERIALS SCIENCE 42 ( 17 ) 7604 - 7606 2007.9 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC Joint Work
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Seeds Innovation and Bearing Applications of Silicon Nitride Ceramics
Junichi Tatami, Katsutoshi Komeya
Key Engineering Materials 352 147 - 152 2007.8 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Silicon nitride (Si3N4) is one of the most attractive materials for wear applications because it has excellent wear resistance and offers advantages such as light weight, higher strength and toughness, and good corrosion resistance. In 1984, Materials Div., Toshiba Corp. (today, Toshiba Materials Co., Ltd.) and Koyo Seiko Co. Ltd. (today JTEKT Corp.) successfully utilized high-strength silicon nitride for anti-friction bearings for the first time in the world.1-3 This ceramic bearing was a most successful product and has expanded in area and volume through key innovations such as pioneered compositions, further improvement of durability against a steel ball and the development of a conventional fabrication process. Since 1989, Yokohama National University group has investigated new materials development in silicon nitride ceramics, densification/strengthening mechanisms in an optimized sintering aids system, powder processing for reliable components and tribological evaluation for bearing applications. Subsequently it was confirmed that the addition of TiO2 and AlN to an Si3N4-Y2O3-Al2O3 system promoted densification at low temperatures.4 During firing, the TiO2 changed into TiN at the grain boundary, causing grain boundary strengthening.5,6 Most recently, it has developed a carbon nanotube (CNT) dispersed silicon nitride with high strength and high electrical conductivity that is expected to open up new applications as a new functional silicon nitride.7 However, there are many items to be overcome toward the future, which are the development of cost reduction processes with higher material reliability, and the opening up of new applications supported by validated evaluation techniques including tribology, flaw detection and life prediction, raw powder problems related to cost and production volume, and the classification of silicon nitride bearings for various graded applications.</jats:p>
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Liquid Phase Sintering of Aluminum Nitride
Katsutoshi Komeya, Junichi Tatami
Materials Science Forum 554 181 - 188 2007.8
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Liquid-phase sintering of aluminum nitride (AlN) with additives was reviewed. The most important innovation was the discovery of critical sintering aids for AlN densification, specifically rare-earth compounds and alkali-earth compounds. These additives are extremely valuable for increasing thermal conductivity by trapping and removing oxygen in the AlN lattice during firing. Consequently, thermal conductivities in AlN ceramics of 100 to 260W/mK were developed. We also studied the effects of parameters such as raw powder, additives, composition, and firing condition in liquid-phase sintering with AlN-sintering aids, focusing on oxygen impurities in the system. The sintering behavior of powder compacts was investigated by evaluating the densification, the lattice constant c for AlN, and the dihedral angle of the interface between the AlN grains and the grain boundary liquid-phase. In our results, the change in densification was closely related to changes in the lattice constant c and the dihedral angle. That is, the sintered density increased with an increase in the oxygen dissolved in the AlN grains and with the improvement in wettability between the solid and liquid phase.</jats:p>
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Yokoyama T., Meguro T., Shimada Y., Tatami J., Komeya K., Abe Y.
JOURNAL OF MATERIALS SCIENCE 42 ( 14 ) 5860 - 5866 2007.7 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Li, Feng Jin; Wakihara, Toru; Tatami, Junichi; Komeya, Katsutoshi; Meguro, Takeshi
J. Eur. Ceram. Soc. 27 ( 6 ) 2535 - 2540 2007.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Fabrication of transparent SiO2 glass from pressureless sintering of floc-cast green body in air
Hiratsuka Daisuke, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 115 ( 1342 ) 392 - 394 2007.6 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
We prepared dense (67.9 vol%) green bodies from high-purity spherical fused SiO<sub>2</sub> powder by using the floc-casting technique. A firing schedule was determined from data obtained by the <i>in-situ</i> measurement of the sintering shrinkage of the compacts. Accordingly, we fired the compacts at 1400°C for 30 min in air to obtain transparent SiO<sub>2</sub> glass sintered bodies. The XRD patterns of the sintered bodies were the same as those before sintering. No crystallization was observed in the sintered bodies. Moreover, the sintered bodies with a thickness of 2 mm had a high transmissivity (>85%) in the visible range.<br>
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Elucidation of the formation mechanism of beta-SiAlON from a zeolite
Li Feng Jin, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Mackenzie Kenneth J. … Show more authors
Li Feng Jin, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Mackenzie Kenneth J. D. Hide authors
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 90 ( 5 ) 1541 - 1544 2007.5 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>β‐SiAlON was synthesized from Y‐type zeolite and its formation mechanism was determined using magic‐angle spinning nuclear magnetic resonance (NMR) spectroscopy and powder X‐ray diffraction (XRD). Y‐type zeolite and carbon powders were mixed for 36 h, fired at 1050° to 1450°C for 0–2 h in flowing gas (0.5 L/min N<jats:sub>2</jats:sub>), then heat treated at 700°C for 2 h in air to remove residual carbon. The resulting product was, according to XRD analysis, mono‐phase β‐SiAlON; but minor amounts of unreacted SiO<jats:sub>2</jats:sub> and SiC (possibly amorphous) were detected in the NMR spectra. It was found that β‐SiAlONs with higher and lower Z values are formed by different reaction pathways.</jats:bold> </jats:p>
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Nitridation of silica characterized by high-energy X-ray diffraction technique
Wakihara Toru, Yamakawa Tomohiro, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kohara Shinji
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 90 ( 5 ) 1562 - 1565 2007.5 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>The structure of amorphous silicon oxynitride formed under nitridation conditions using ammonia gas, before the onset of silicon nitride crystallization, is determined employing high‐energy X‐ray diffraction (HEXRD) technique. The derived real‐space function suggests that smaller ring structures, especially 3R and 4R (R: ring), which are the dominant rings in crystalline silicon nitride, are not major species in amorphous silicon oxynitride, and form in the latter part of the silicon nitride crystallization.</jats:bold> </jats:p>
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High-temperature deformation of alpha-SiAlON nanoceramics without additives
Chihara Kentarou, Hiratsuka Daisuke, Tatami Junichi, Wakai Fumihiro, Komeya Katsutoshi
SCRIPTA MATERIALIA 56 ( 10 ) 871 - 874 2007.5 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
A Ca-α SiAlON nanoceramic was fabricated from Ca0.8Si9.6Al2.4O0.8N15.2 nanopowder without using any sintering additive. The flow stress of the SiAlON nanoceramic, which contained almost no glass phase, was higher than that of liquid phase sintered SiAlONs containing a large amount of glass phase. The deformation was characterized by Newtonian flow in a wide range of stresses, and shear-thickening creep, which has been reported in liquid containing SiAlONs, was not observed.
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Improving the microstructure of Si3N4-TiN composites using various PEIs to disperse raw TiO2 powder
S. Zhang, L. Gao, J. Tatami, H.Watanabe, T. Wakihara, T. Meguro, K. Komeya
Ceramics International 33 ( 3 ) 355 - 359 2007.4 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of Ca-.ALPHA. SiAlON using Zeolite as a Raw Material
Journal of the Ceramic Society of Japan 115 ( 1340 ) 294 - 296 2007.4 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Improving the microstructure of Si3N4–TiN composites using various PEIs to disperse raw TiO2 powder
Shan Zheng, Lian Gao, Hiroshi Watanabe, Junichi Tatami, Toru Wakihara, Katsutoshi Komeya, Takeshi M … Show more authors
Shan Zheng, Lian Gao, Hiroshi Watanabe, Junichi Tatami, Toru Wakihara, Katsutoshi Komeya, Takeshi Meguro Hide authors
Ceramics International 33 ( 3 ) 355 - 359 2007.4
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
An in situ synthesis route was developed for the preparation of dense and homogenous Si3N4–TiN (5 vol% TiN) composites, with TiN grains formed from TiO2 and AlN. The dispersion of TiN grains in the Si3N4 matrix using various polyethyleneimines (PEIs) as dispersing agents for raw TiO2 powder was investigated by scanning electron microscopy (SEM). We found that the microstructure of Si3N4–TiN composites was improved with the aid of PEI to disperse TiO2 particles in the mixture. It was critical to disperse original TiO2 particles with the appropriate dispersant before the sintering process, because the size of TiN grains in the Si3N4–TiN composites was strongly dependent on the size of TiO2 particles. PEI molecules modified the surface of TiO2 particles and protected the TiO2 particles in the slurry from aggregations. It was a practical and useful way to obtain the Si3N4–TiN composites with homogeneous microstructures without the alteration of the preparation procedure.
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Fabrication and Evaluation of AlN-SiC Solid Solutions by Spark Plasma Sintering Technique
TATAMI Junichi, KOBAYASHI Ryota, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi, TU Rong, GOTO Ta … Show more authors
TATAMI Junichi, KOBAYASHI Ryota, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi, TU Rong, GOTO Takashi Hide authors
59 ( 3 ) 152 2007.3
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10018736639
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Feng Jin Li, Toru Wakihara, Junichi Tatami, Katsutoshi Komeya, Takeshi Meguro
Journal of the European Ceramic Society 27 ( 6 ) 2535 - 2540 2007.1
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract β-SiAlON was synthesized from select zeolite Y compositions with different Si/Al ratios by carbothermal reduction–nitridation (CRN), and the correlation between the starting compositions and products was investigated. The carbon content in all of the zeolite samples was fixed at 1.2 times the required stoichiometric value. Zeolite–carbon mixtures were placed in a carbon boat and fired in a furnace at 1300 °C for 0 min, and 1450 °C for 0, 120 min in a N 2 flow of 0.5 l/min. The main phase in each of the samples fired at 1450 °C for 120 min was determined from XRD results as β-SiAlON. It was also found that the ratio of β-SiAlON to minor phases such as α-Si 3 N 4 and Si 2 N 2 O is typically higher in samples prepared from zeolites rather than from silica–alumina mixtures of the same compositions. This indicates that zeolites are ideal raw materials for the CRN synthesis of high purity β-SiAlONs by CRN with various z values.
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Liquid phase sintering of aluminum nitride
Komeya K., Tatami J.
NITRIDES AND OXYNITRIDES III 554 181 - + 2007
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Zheng Shan, Gao Lian, Watanabe Hiroshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Ta … Show more authors
Zheng Shan, Gao Lian, Watanabe Hiroshi, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
INNOVATION IN CERAMICS SCIENCE AND ENGINEERING 352 115 - + 2007
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Dense and homogenous Si3N4-TiN composites (5 vol% TiN) were prepared by using in situ synthesis method from Si3N4, AlN and TiO2 mixtures, containing Y2O3 and Al2O3 as sintering aids. In the prepared Si3N4-TiN composites, TiN grains were formed from TiO2 and AlN powders during the sintering process, in which ammonium citrate was used as a dispersant for raw TiO2 powders. The microstructures of the Si3N4-TiN composites with the increase of ammonium citrate were investigated by scanning electron microscopy (SEM). Citrate ions modified on the surface of TiO2 particles and protected the TiO2 particles in the mixed slurry to reduce the aggregations of TiO2 powders, and homogenous Si3N4-TiO2-AlN composite powder was prepared for sintering. The microstuctures of Si3N4-TiN were developed after sintering with the uniform distribution of TiN grains in the Si3N4 ceramics. It was found that the microstructure of Si3N4-TiN composite was improved significantly with 0.20 g ammonium citrate in the system, TiN grains with 0.2-0.3 μm in diameter distributed throughout Si3N4 matrix. It was a practical and useful way to improve the microstructure of Si3N4-TiN composite without the alteration of the preparation procedure.</jats:p>
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horikawa daisuke, tatami junichi, wakihara toru, komeya Katsutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 68 - 68 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006970817
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Electrical properties of Mn-Co-Ni oxides prepared at low temperatures
Yokoyama T., Meguro T., Okazaki S., Fujikawa H., Ishikawa T., Tatami J., Wakihara T., Komeya K., Sa … Show more authors
Yokoyama T., Meguro T., Okazaki S., Fujikawa H., Ishikawa T., Tatami J., Wakihara T., Komeya K., Sasamoto T. Hide authors
ADVANCED MATERIALS AND PROCESSING IV 29-30 359 - + 2007
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Changes in crystal phase and electrical properties of oxides composed of Mn, Co, and Ni with the molar ratios of 5:2:1 and 3:3:1 were investigated. Starting oxides were fired from 250°C to 800°C, then maintained at prescribed temperatures for 3 h in air. In the 5:2:1 specimen, a monophase consisting of a cubic spinel oxide that is important to electrical conductivity was obtained at firing temperature of 800°C. In the 3:3:1 specimen, the monophase was obtained at temperatures ranging from 600°C to 800°C. Electrical resistance decreased exponentially with increasing temperature for all specimens fired at temperatures ranging from 250°C to 800°C, indicating that the oxides have intrinsic thermistor characteristics with negative temperature coefficient (NTC). The temperature dependence of the thermistor constant (B value) necessary for practical application was considered to be related to the existence ratio of cubic spinel-type and ilmenite-type structures and the lattice constant of the cubic spinel-type structure. The electrical conduction was stabilized by annealing at prescribed temperatures for more than 720 minutes.</jats:p>
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Effect of diluents on post-reaction sintering of silicon nitride ceramics
Wakihara Toru, Yabuki Masahiro, Tatami Junichi, Korneya Katsutoshi, Meguro Takeshi, Kita Hideki, Ko … Show more authors
Wakihara Toru, Yabuki Masahiro, Tatami Junichi, Korneya Katsutoshi, Meguro Takeshi, Kita Hideki, Kondo Naoki, Hirao Kiyoshi Hide authors
INNOVATION IN CERAMICS SCIENCE AND ENGINEERING 352 185 - + 2007
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Post-reaction sintering as a technique for the fabrication of Si3N4 ceramics has received much attention as a cost-effective process due to the use of cheap Si powder as a raw material. In this method, the rapid exothermic nitridation of Si results in local melting of Si to cause its agglomeration, which is expected to be a flaw after densification. Therefore, control of the exothermic reaction is needed to improve the reliability of post-reaction sintered Si3N4 ceramics. In this study, Si3N4 ceramics were fabricated by post-reaction sintering with Si3N4 or SiO2 powders in order to control the exothermic reaction. As a result, the microstructure and bending strength of Si3N4 ceramics was changed by adding these additives. In particular, the addition of SiO2 resulted in the high strength of Si3N4 ceramics. Consequently, it was found that Si3N4 and SiO2 particles played the role of diluents, and SiO2 was effective in post-reaction sintering as an oxygen donor.</jats:p>
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Tribology properties of CNT Dispersed Silicon Nitride Ceramics
Takahashi Kenji, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Azushima Akira
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 289 - 289 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973372
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Wear behavior of CNT Dispersed Si<SUB>3</SUB>N<SUB>4</SUB> Ceramics
Takahashi Kenji, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Azushima Akira
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 376 - 376 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974447
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Mechanical properties of a-,b-SiAlON composite ceramics fabrocated b-SiAlON powder
Asakoshi Kei, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Yokouchi Masahiro
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 70 - 70 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006970777
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509 Hybrid Nano-fractography of Ceramics by Scanning Probe Microscope
Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
The Proceedings of the Materials and processing conference 2007 ( 0 ) 329 - 330 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Japan Society of Mechanical Engineers Joint Work
In this study, nano-scale observation of a crack and a fracture surface of using scanning probe microscope was applied to the ferroelectric and the ferromagnetic ceramics. Smultaneous observation of a profile and a property of a crack and a fracture surface was carried out using piezoelectric force microscope (PFM), scanning nonlinear dielectric microscope (SNDM), and magnetic force microscop (MFM), which is named "Hybrid nano-fractography". In BaTiO_3 ceramics, Only domain with unidirectional polarization was observed on the fracture surface by SNDM, which is different from the PRM image. It was also shown that the domain structure was changed near the crack tip by crack propagation. It is because that the local domain switching induced by stress concentration near the crack tip. In Mn-Zn ferrite ceramics, it was shown that a crack induced by Vickers indentation was not open and there was a small step along the crack from the topo image. The magnetic force image indicated that there is the magnetic domain where magnetic polarity reversed near the crack.
Other Link： https://ci.nii.ac.jp/naid/110007083782
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Seeds innovation and bearing applications of silicon nitride ceramics
Komeya Katsutoshi, Tatami Junichi
INNOVATION IN CERAMICS SCIENCE AND ENGINEERING 352 147 - + 2007
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Mechanical properties and microstructure of high thermal conductive AlN ceramics
Doi Masamune, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 290 - 290 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973374
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wakihara toru, kohara shinji, tatami junichi, komeya katsutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 407 - 407 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975027
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Microstructure observation of ZnO ceramics by scanning nonlinear dielectric microscope
Tasaki Satoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 315 - 315 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973101
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Synthesis and formation mechanism of b-sialon prepared by reduction nitridation method
wakihara toru, Saito Yuri, tatami junichi, komeya katsutoshi, meguro takeshi, Kenneth Mackenzie
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 120 - 120 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971790
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Observation of local electric properties of ZnO ceramics by Scanning Nonlinear Dielectric Microscope
tasaki satoko, tatami junichi, wakihara toru, komeya katutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 248 - 248 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972446
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A new approach to the master sintering curve theory for viscous flow sintering system
HIRATSUKA Daisuke, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 209 - 209 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973637
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KODAMA ERIKO, TATAMI JUNICHI, WAKIHARA TORU, KOMEYA KATUTOSHI, MEGURO TAKESHI, NAKANO HIROMI
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 20 - 20 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971907
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TATAMI Junichi, WATANABE Hiroshi, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi
THE MICROMERITICS 51 ( 0 ) 52 - 56 2007 [Reviewed]
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Hosokawa Micron Corporation Joint Work
Other Link： https://ci.nii.ac.jp/naid/130007495399
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KODAMA ERIKO, TATAMI JUNICHI, WAKIHARA TORU, KOMEYA KATHUTOSHI, MEGURO TAKESHI, AZUSHIMA AKIRA
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 288 - 288 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973364
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Hybrid nano-fractography of Mn-Zn ferrite by magnetic force microscopy
Tatami Junichi, Tatsumi Yui, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 762 - 762 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972744
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HIRATSUKA Daisuke, TATAMI Junichi, WAKIHARA Toru, KOMEYA Katsutoshi, MEGURO Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 19 - 19 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971612
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Kondo Mitsuhiro, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 573 - 573 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971389
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High-temperature Strength of AlN-SiC Ceramics fabricated by Spark Plasma Sintering
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Ta … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Takashi, Chen I-Wei Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 292 - 292 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973375
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Evaluation of corrosion resistance of reaction-sintered silicon carbide in sulfuric acid
Kinoshita Ayako, Tatami Junichi, Wakihara Toru, Komeya Masatoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 480 - 480 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Corrosion resistance of reaction-sintered silicon carbide (RS-SiC) was investigated. Corrosion test was carried out in sulfuric acid at 80 degree for 1000 hours. The weight of RS-SiC after corrosion test slightly decreased because of SiO2 protection layer. The bending strength of the corroded RS-SiC was almost the same as that before corrosion test.
Other Link： https://ci.nii.ac.jp/naid/130006973514
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Tatami Junichi, Matsuzawa Nanako, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 339 - 339 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973314
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Yabuki Hiromasa, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kondou Naoki, Hy … Show more authors
Yabuki Hiromasa, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Kondou Naoki, Hyuga Hideki, Kita Hideki Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 564 - 564 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Post-reaction sintering technique is one of the fabrication process of Si<SUB>3</SUB>N<SUB>4</SUB> ceramics, which has received much attention as cost-effective process due to using cheap Si powder as a raw material. Many researches on the development of this method have been performed, so far, in order to improve their properties; however, sintering shrinkage behavior, which is very important information to optimize the firing condition, has not been well clarified. In this study, we focused on post-reaction sintering technique of Si-Y<SUB>2</SUB>O<SUB>3</SUB>-Al<SUB>2</SUB>O<SUB>3</SUB> system, and investigated its sintering shrinkage behavior by dilatometory.
Other Link： https://ci.nii.ac.jp/naid/130006971422
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Hybrid Nanofractography of BaTiO3 Ceramics
NAKADA SATOSHI, TATAMI JUNICHI, WAKIHARA TORU, KOMEYA KATSUTOSHI, TASAKI SATOKO, MEGURO TAKESHI
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 495 - 495 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974350
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wakihara toru, yamakawa tomohiro, kohara shinji, tatami junichi, komeya katsutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 194 - 194 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973893
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Synthesis of b-SiAlON phosphor powder by reduction nitridation of a zeolite
saito yuri, wakihara toru, tatami junichi, komeya katsutoshi, meguro takeshi, Fukuda Yumi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 398 - 398 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974991
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Tatami Junichi, Yamamoto Yohei, Komeya Katsutoshi, Wakihara Toru, Meguro Takeshi, I-Wei Chen, Komat … Show more authors
Tatami Junichi, Yamamoto Yohei, Komeya Katsutoshi, Wakihara Toru, Meguro Takeshi, I-Wei Chen, Komatsu Michiyasu, Do-Kyung Kim Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2007 ( 0 ) 198 - 198 2007
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
The fracture resistance curve and Hertzian contact fatigue test of TiN particle dispersed Si3N4 ceramics were carried out. The Si3N4 ceramics without TiN showed a typical R-curve, that is the KR was initially around 5.5 MPam1/2, it increased during fracture and it achieved 6.5MPam1/2 at the crack extension of 300m. On the other hand, Si3N4 ceramics with TiN particles has higher initial KR value and their R-curve indicated less slop than that without TiN. Although the strength of the Si3N4 ceramics without TiN degraded after cyclic indentation, that of TiN particle dispersed Si3N4 ceramics maintained because of limited crack generation and extension. The cyclic contact fatigue was explained by the difference in R-curve behavior.
Other Link： https://ci.nii.ac.jp/naid/130006973883
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Seeds innovation and bearing applications of silicon nitride ceramics
Komeya, K. and Tatami, J.
Key Engineering Materials 352 147 - 152 2007
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Liquid phase sintering of aluminum nitride
Komeya, K. and Tatami, J.
Materials Science Forum 554 181 - 188 2007
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Kinetics of gasification of glass-like carbons heat-treated at various temperatures with CO2
Hirasaki, T. and Meguro, T. and Tatami, J. and Wakihara, T. and Komeya, K.
Journal of Ceramic Processing Research 8 ( 1 ) 12 - 18 2007 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Zheng, S. and Gao, L. and Watanabe, H. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Key Engineering Materials 352 115 - 118 2007
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Electrical properties of Mn-Co-Ni oxides prepared at low temperatures
Yokoyama, T. and Meguro, T. and Okazaki, S. and Fujikawa, H. and Ishikawa, T. and Tatami, J. and Wa … Show more authors
Yokoyama, T. and Meguro, T. and Okazaki, S. and Fujikawa, H. and Ishikawa, T. and Tatami, J. and Wakihara, T. and Komeya, K. and Sasamoto, T. Hide authors
Advanced Materials Research 29-30 359 - 362 2007
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Effect of diluents on post-reaction sintering of silicon nitride ceramics
Wakihara, T. and Yabuki, M. and Tatami, J. and Komeya, K. and Meguro, T. and Kita, H. and Kondo, N. … Show more authors
Wakihara, T. and Yabuki, M. and Tatami, J. and Komeya, K. and Meguro, T. and Kita, H. and Kondo, N. and Hirao, K. Hide authors
Key Engineering Materials 352 185 - 188 2007
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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CNT分散Si_3N_4セラミックスのトライボロジー特性
多々見 純一, 脇原 徹, 米屋 勝利
日本セラミックス協会2007年年会講演予稿集 145 2007 [Invited]
Language：The in addition, foreign language Publishing type：Research paper (research society, symposium materials, etc.) Joint Work
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先進セラミックスプロセッシング
多々見 純一, 米屋 勝利
テクニカルショウヨコハマ 2007 [Invited]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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研究室発!! New 技術シーズ
多々見 純一, 米屋 勝利
化学装置 2007 [Invited]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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走査型プローブ顕微鏡によるセラミックスのハイブリッドナノフラクトグラフィー
多々見 純一
第15回機械材料・材料加工技術講演会(M&P2007) 2007 [Invited]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Single Work
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Improving the microstructure of Si3N4-TiN composites using various PEIs to disperse raw TiO2 powder
Zheng, Shan and Gao, Lian and Watanabe, Hiroshi and Tatami, Junichi and Wakihara, Toru and Kom … Show more authors
Zheng, Shan and Gao, Lian and Watanabe, Hiroshi and Tatami, Junichi and Wakihara, Toru and Komeya, Katsutoshi and Meguro, Takeshi Hide authors
Ceramics International 33 ( 3 ) 355 - 359 2007 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of beta-SiAlON powder by carbothermal reduction-nitridation of zeolites with different compositions
Li, Feng Jin and Wakihara, Toru and Tatami, Junichi and Komeya, Katsutoshi and Meguro, Takeshi
Journal of the European Ceramic Society 27 ( 6 ) 2535 - 2540 2007 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of AlN powder from Al(OH)3 by reduction-nitridation in a mixture of NH3-C3H8 gas
T. Yamakawa, J. Tatami K. Komeya, T. Meguro
J. Eur. Ceram. Soc. 26 ( 12 ) 2413 - 2418 2006.12 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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多々見 純一, 米屋 勝利
Material stage / 技術情報協会 編 6 ( 9 ) 67 - 74 2006.12
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：技術情報協会 Joint Work
コレクション : 国立国会図書館デジタルコレクション > デジタル化資料 > 雑誌
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Fracture Resistance and Contact Damage of TiN Particle Reinforced Si3N4 Ceramics
J. Tatami, I.-W. Chen, Y. Yamamoto, M. Komatsu, K. Komeya, D.K. Kim, T. Wakihara and T. Meguro
J. Ceram. Soc. Japan 114 ( 11 ) 1049 - 1053 2006.11 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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研究室発!! NEW技術シーズ(第5回)焼結挙動の評価・解析・制御とセラミックスの高機能化・高信頼性化
多々見 純一, 米屋 勝利
化学装置 48 ( 10 ) 9 - 11 2006.10
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：工業調査会 Joint Work
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Electrical Properties of AlN-SiC Ceramics
Junichi Tatami, Katsutoshi Komeya, Takeshi Meguro, Ryota Kobayashi, Toru Wakihara
Key Engineering Materials 317-318 641 - 644 2006.8 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>AlN-SiC ceramics with 0 to 75 mol% of AlN were fabricated through pressureless sintering of very fine AlN and SiC. Powder compacts with different amounts of AlN were fired at 2000°C for 1 h in Argon gas flow using an induction-heating furnace. The microstructure and phases present in the products were evaluated using SEM and XRD. The AlN-SiC ceramics had a porous structure with 30% porosity, and the grain size was increased with the addition of AlN. XRD analysis showed that 2H was a main phase in all samples, though 3C and 6H phases were found in 25 mol%AlN-75 mol%SiC ceramic. The electrical properties of the AlN-SiC ceramics were evaluated at various temperatures ranging from room temperature to 300°C. The electrical conductivity of the AlN-SiC ceramics depended on the amount of AlN and on the temperature. The 75 mol%AlN-SiC ceramic had higher electrical resistance, though the other samples were electrical conductors. The highest electrical conductivity was obtained with the 25 mol% AlN composition, which was 7 S/m at room temperature and 30 S/m at 300°C. The Seebeck coefficient for the AlN-SiC ceramics increased with rising temperatures. The AlN-SiC ceramics with 50 mol%AlN had the highest Seebeck coefficient of 220 2V/K at 300°C.</jats:p>
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Electrical properties of AlN-SiC ceramics
R. Kobayashi, J. Tatami, T. Wakihara, T. Meguro, K. Komeya
Key Engineering Materials 317-318 641 - 644 2006.8
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Control of shrinkage during sintering of alumina ceramics based on Master Sintering Curve theory
J. Tatami, Y. Suzuki, T. Wakihara, T. Meguro, K. Komeya
Key Engineering Materials 317-318 11 - 14 2006.8
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Formation mechanism of nano AlN powder by gas-reduction-nitridation
T. Yamakawa, J. Tatami, T. Wakihara, K. Komeya, T. Meguro, KJD MacKenzie
Key Engineering Materials 317-318 215 - 218 2006.8
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of β-SiAlON nanoceramics
D. Hiratsuka, J. Tatami, T. Meguro, K. Komeya, I. Hayashi, JF Yang, M. Omori
Key Engineering Materials 317-318 633 - 636 2006.8
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Effect of the microstructureOf Si3N4 on the adhesion strength of TiN film on Si3N4
Kim Young-Gu, Tatami Junichi, Komeya Katsutoshi, Kim Do Kyung
THIN SOLID FILMS 510 ( 1-2 ) 222 - 228 2006.7 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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TASHIRO Yoshikazu, KATSUMI Yoshimasa, FUJII Yasuki, KUBO Masahiro, MEGURO Takeshi, TATAMI Junichi, … Show more authors
TASHIRO Yoshikazu, KATSUMI Yoshimasa, FUJII Yasuki, KUBO Masahiro, MEGURO Takeshi, TATAMI Junichi, KOMEYA Katsutoshi Hide authors
Materials science and technology 43 ( 2 ) 93 - 98 2006.4 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10024351859
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Temperature dependence of the electrical properties and seebeck coefficient of AlN-SiC ceramics
R. Kobayashi, J. Tatami, T. Wakihara, T. Meguro, K. Komeya
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 89 ( 4 ) 1295 - 1299 2006.4 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Contact damage behavior of TiN-coated Si3N4 ceramics
Ceramic Transactions 146 409 - 415 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Sintering behavior of AlN
Ceramic Transactions 146 299 - 306 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microstructure of AlN fibers synthesized from Al2O3 by gas-reduction-nitridation
Ceramic Transactions 146 291 - 297 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microstructure and mechanical properties of AlN ceramics with Y2O3
Ceramic Transactions 146 285 - 290 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Characteristics of dehumidifier sheets for an adsorptive desiccant cooling system
Ceramic Transactions 146 199 - 205 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Fabrication, microstructure, and corrosion resistance of b-sialon nano-ceramics
Ceramic Transactions 146 193 - 198 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effects of a phase content on the sintering behavior of Si3N4 powder
Ceramic Transactions 146 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of AlN by gas-reduction-nitridation of transition alumina powder
Yamakawa, Tomohiro; Tatami, Junichi; Meguro, Takeshi; Komeya, Katsutoshi
Ceramic Transactions 146 179 - 186 2006.3 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Changes in Microstructure of Activated Carbons Introduced by Heat Treatment
Amaoka Toshikazu, Meguro Takeshi, Tatami Junichi, WAKIHARA Jyunichi, KOMEYA Katutoshi, HOTTA Noriya … Show more authors
Amaoka Toshikazu, Meguro Takeshi, Tatami Junichi, WAKIHARA Jyunichi, KOMEYA Katutoshi, HOTTA Noriyasu Hide authors
材料の科学と工学 = Materials science and technology 43 ( 1 ) 38 - 42 2006.2 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：日本材料科学会 Joint Work
Other Link： https://ci.nii.ac.jp/naid/10024351719
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Temperature Dependence of the Electrical Properties and Seebeck Coefficient of AlN–SiC Ceramics
Ryota Kobayashi, Junichi Tatami, Toru Wakihara, Takeshi Meguro, Katsutoshi Komeya
Journal of the American Ceramic Society 89 ( 4 ) 1295 - 1299 2006.2
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>AlN–SiC ceramics composed of AlN–SiC solid solutions were fabricated by pressureless sintering without sintering additives. The microstructure and electrical properties of the AlN–SiC ceramics were investigated for compositions between 0 and 75 mol% AlN. The AlN–SiC ceramics had a porous structure, and a 2H polytype was found in all compositions. The electrical conductivities and Seebeck coefficients of the AlN–SiC ceramics increased with temperature. The electrical conductivity of 25 mol% AlN–75 mol% SiC ceramics was the highest in all compositions: 32.7 S/m at 300°C. In contrast, the electrical conductivity of 75 mol% AlN–25 mol% SiC ceramics was much lower than that of other samples: 10<jats:sup>−2</jats:sup> S/m at 300°C. The Seebeck coefficient of 50 mol% AlN–50 mol% SiC ceramics was the highest of all samples: 210 μV/K at 300°C. The electrical and thermoelectrical properties of SiC can be controlled by the formation of AlN–SiC solid solutions.</jats:bold> </jats:p>
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Synthesis of AlN nanopowder from gamma-Al2O3 by reduction-nitridation in a mixture of NH3-C3H8
Yamakawa T, Tatami J, Wakihara T, Komeya K, Meguro T, MacKenzie KJD, Takagi S, Yokouchi M
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 89 ( 1 ) 171 - 175 2006.1 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p><jats:bold>Aluminum nitride (AlN) powders were synthesized by gas reduction–nitridation of γ‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>using NH<jats:sub>3</jats:sub>and C<jats:sub>3</jats:sub>H<jats:sub>8</jats:sub>as the reactant gases. AlN was identified in the products synthesized at 1100°–1400°C for 120 min in the NH<jats:sub>3</jats:sub>–C<jats:sub>3</jats:sub>H<jats:sub>8</jats:sub>gas flow confirming that AlN can be formed by the gas reduction–nitridation of γ‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>. The products synthesized at 1100°C for 120 min contained unreacted γ‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>. The<jats:sup>27</jats:sup>A1 MAS NMR spectra show that Al–N bonding in the product increases with increasing reaction temperature, the tetrahedral AlO<jats:sub>4</jats:sub>resonance decreasing prior to the disappearance of the octahedral AlO<jats:sub>6</jats:sub>resonance. This suggests that the tetrahedral AlO<jats:sub>4</jats:sub>sites of the γ‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>are preferentially nitrided than the AlO<jats:sub>6</jats:sub>sites. AlN nanoparticles were directly formed from γ‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>at low temperature because of this preferred nitridation of AlO<jats:sub>4</jats:sub>sites in the reactant. AlN nanoparticles are formed by gas reduction–nitridation of γ‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>not only because the reaction temperature is sufficiently low to restrict grain growth, but also because γ‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>contains both AlO<jats:sub>4</jats:sub>and AlO<jats:sub>6</jats:sub>sites, by contrast with α‐Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>which contains only AlO<jats:sub>6</jats:sub>.</jats:bold></jats:p>
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Synthesis of AlN powder from Al(OH)3 by reduction–nitridation in a mixture of NH3–C3H8 gas
Tomohiro Yamakawa, Junichi Tatami, Katsutoshi Komeya, Takeshi Meguro
Journal of the European Ceramic Society 26 ( 12 ) 2413 - 2418 2006.1
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Elsevier BV Joint Work
Abstract Aluminum nitride (AlN) powders were synthesized by gas-reduction–nitridation of aluminum hydroxide (Al(OH)3) powders using a mixture of NH3 and C3H8 gases. A high conversion to AlN (over 70% of naitridation ratio) and single-phase AlN were achieved over 1200 °C. The specific surface area of the products decreased with increasing of reaction temperature and soaking time, and products obtained contain much lesser oxygen than those of the previous researches. The reason why such nanosized AlN powders were easily obtained from Al(OH)3 was considered to be the higher surface areas of transition alumina formed by dehydration of Al(OH)3 during firing.
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Sintering shrinkage behavior of HfO2 added Si3N4
horikawa daisuke, tatami junichi, wakihara toru, komeya katsutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 311 - 311 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006970434
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Fabrication and Evaluation of CNT dispersed Si3N4 ceramics
Yoshio Sara, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 308 - 308 2006 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972126
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Synthesis and evalution of AlN based phosphors
Abe Shoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Fukuda Yumi, Albessard … Show more authors
Abe Shoko, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Fukuda Yumi, Albessard Ariane Keiko, Mitsuishi Iwao Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 133 - 133 2006 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973554
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Microstructure control of porous AlN polytypoid
Kato Koji, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 309 - 309 2006 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
The system in Si-Al-O-N has some types of AlN polytypoids based on AlN structure. AlN polytypoids have characteristic structures with different stacking periods in the direction of c-axis corresponding to the amount replaced Al, N by Si, O. We focused on controlling microstructures of the porous AlN polytypoids ceramics which are fabricated by utilizing their anisotropic plate-like grain growth. In this study, the effects were investigated of raw materials, compositions and firing temperatures on porous AlN polytypoid ceramics. Consequently, a variety of porous AlN polytypoid ceramics can be fabricated by controlling them
Other Link： https://ci.nii.ac.jp/naid/130006970454
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Thermoelectrical properties of Al-Si-C-N solid solutions
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Gtou Takashi, To … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Gtou Takashi, To Yo Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 393 - 393 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006975148
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YABUKI HIROMASA, WAKIHARA TORU, TATAMI JUNICHI, KOMEYA KATSUTOSHI, MEGURO TAKESHI, KONDO NAOKI, HYU … Show more authors
YABUKI HIROMASA, WAKIHARA TORU, TATAMI JUNICHI, KOMEYA KATSUTOSHI, MEGURO TAKESHI, KONDO NAOKI, HYUGA HIDEKI, KITA HIDEKI Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 231 - 231 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972745
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Sintering behaviour and Microstructure of High Mobility ZnO ceramics
Tasaki Satoko, Tatami Junichi, Wakihara Toru, Komeya Toshinori, Meguro Takeshi, Mizutani Makoto
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 184 - 184 2006 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971184
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Nitridation process of amorphous silica characterized by high-energy X-ray diffraction technique
Wakihara Toru, Yamakawa Tomohiro, Kohara Shinji, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 116 - 116 2006 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971622
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Tatami Junichi, Watanabe Hiroshi, Wakihara Toru, Komeya Katsutoshi, Azushima Akira, Aramaki Kenji, … Show more authors
Tatami Junichi, Watanabe Hiroshi, Wakihara Toru, Komeya Katsutoshi, Azushima Akira, Aramaki Kenji, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 277 - 277 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972041
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In-situ measurement of sintering behavior of Porous Silicon carbide ceramics
matsuzawa nanako, Kobayashi Ryota, tatami jyuniti, wakihara toru, komeya katunori, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 65 - 65 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973043
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matsuzawa nanako, kobayashi ryouta, tatami jyunichi, wakihara toru, komeya katutoshi, meguro takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 234 - 234 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972457
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High temperature deformation of SiAlON prepared without using additives
CHIHARA Kentarou, INABA Kenichi, SHINODA Yutaka, AKATSU Takashi, WAKAI Fumihiro, HIRATSUKA Daisuke, … Show more authors
CHIHARA Kentarou, INABA Kenichi, SHINODA Yutaka, AKATSU Takashi, WAKAI Fumihiro, HIRATSUKA Daisuke, TATAMI Junichi, KOMEYA Katsutoshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 251 - 251 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972488
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Extension of Master Sintering Curve Theory to Viscous Flow
Hiratsuka Daisuke, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 560 - 560 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006970335
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Control of sintering shrinkage behavior in ceramics based on master sintering curve theory
Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 491 - 491 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974353
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Analysis of Sintering Behavior of Alumina Nano Particles Based on Master Sintering Curve Theory
Hashizume Kousuke, Hiratsuka Daisuke, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Take … Show more authors
Hashizume Kousuke, Hiratsuka Daisuke, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 313 - 313 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972112
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Analysis of Sintering Behavior of AlN Nano Particles by Master Sintering Curve Theory
Sakaguchi Yoshikazu, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 312 - 312 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972114
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Fabrication of aluminum silicon carbonitride solid solutions by post-sinter anneling
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Ta … Show more authors
Kobayashi Ryota, Tatami Junichi, Wakihara Toru, Komeya Katsutoshi, Meguro Takeshi, Tu Rong, Goto Takashi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 232 - 232 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972743
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Fabrication of alumina nano particles from furfuryl alcohol-aluminum isopropoxide composite
hirasaki tetsuro, wakihara toru, meguro takeshi, tatami jyunichi, komeya katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 306 - 306 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006970457
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Synthesis of low-z-value high purity bata-SiAlON nanoparticle from high-silica zeolite
Yamakawa Tomohiro, Wakaihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Takagi Shinic … Show more authors
Yamakawa Tomohiro, Wakaihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Takagi Shinichi, Yokouchi Masahiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 431 - 431 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974215
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Formation mechanism of sialons by reduction nitridation of zeolites
wakihara toru, Li Feng-Jin, tatami junichi, Komeya katsutoshi, Meguro Takeshi, MacKenzie Kenneth
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 323 - 323 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972081
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Formation machanism of beta-sialon from zeolite by carbothermal reduction nitridation
Li Fengjin, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, kenneth J.D.Mackenzie
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 512 - 512 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974334
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Synthesis of SiAlON composite ceramics using b'-SiAlON powder
asakoshi kei, yokouchi masahiro
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2006 ( 0 ) 310 - 310 2006
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006970435
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Control of shrinkage during sintering of alumina ceramics based on Master Sintering Curve theory
Tatami, J. and Suzuki, Y. and Wakihara, T. and Meguro, T. and Komeya, K. and Ohji, T and Seki … Show more authors
Tatami, J. and Suzuki, Y. and Wakihara, T. and Meguro, T. and Komeya, K. and Ohji, T and Sekino, T and Niihara, K Hide authors
Science of Engineering Ceramics Iii 317-318 11 - 14 2006
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Yamakawa, T and Tatami, J and Wakihara, T and Komeya, K and Meguro, T and MacKenzie, KJD and … Show more authors
Yamakawa, T and Tatami, J and Wakihara, T and Komeya, K and Meguro, T and MacKenzie, KJD and Takagi, S and Yokouchi, M Hide authors
Journal of the American Ceramic Society 89 ( 2 ) 773 - 773 2006 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Formation mechanism of nano AlN powder by gas-reduction-nitridation
Yamakawa, T. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T. and MacKenzie, K.J.D.
Key Engineering Materials 317-318 215 - 218 2006
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Formation mechanism of nano AlN powder by gas-reduction-nitridation
Yamakawa, T. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T. and MacKenzie, K. J … Show more authors
Yamakawa, T. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T. and MacKenzie, K. J. D. and Ohji, T and Sekino, T and Niihara, K Hide authors
Science of Engineering Ceramics Iii 317-318 215 - 218 2006
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of β-SiAlON nanoceramics
Hiratsuka, D. and Tatami, J. and Meguro, T. and Komeya, K. and Hayashi, I. and Yang, J.-F. and Omor … Show more authors
Hiratsuka, D. and Tatami, J. and Meguro, T. and Komeya, K. and Hayashi, I. and Yang, J.-F. and Omori, M. Hide authors
Key Engineering Materials 317-318 633 - 636 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Hiratsuka, D. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T. and Ibukiyama, M.
Ceramic Transactions 195 107 - 112 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Fabrication and evaluation of beta-SiAlON nanoceramics
Hiratsuka, D. and Tatami, J. and Meguro, T. and Komeya, K. and Hayashi, I. and Yang, J. -F. an … Show more authors
Hiratsuka, D. and Tatami, J. and Meguro, T. and Komeya, K. and Hayashi, I. and Yang, J. -F. and Omori, M. and Ohji, T and Sekino, T and Niihara, K Hide authors
Science of Engineering Ceramics Iii 317-318 633 - 636 2006
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Evaluation of Al-Si-C-N ceramics fabricated by spark plasma sintering
Kobayashi, R. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T. and Goto, T.
Ceramic Transactions 194 273 - 277 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Electrical properties of AlN-SiC ceramics
Kobayashi, R. and Tatami, J. and Wakihara, T. and Meguro, T. and Komeya, K.
Key Engineering Materials 317-318 641 - 644 2006
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Electrical properties of AlN-SiC ceramics
Kobayashi, Ryota and Tatami, Junichi and Wakihara, Toru and Meguro, Takeshi and Komeya, Katsuto … Show more authors
Kobayashi, Ryota and Tatami, Junichi and Wakihara, Toru and Meguro, Takeshi and Komeya, Katsutoshi and Ohji, T and Sekino, T and Niihara, K Hide authors
Science of Engineering Ceramics Iii 317-318 641 - 644 2006
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Effects of process parameters on post reaction sintering of silicon nitride ceramics
Wakihara, T. and Tatami, J. and Komeya, K. and Meguro, T. and Kita, H. and Kondo, N. and Hirao, K.
Ceramic Transactions 195 57 - 63 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Zheng, S. and Gao, L. and Watanabe, H. and Tatami, J. and Wakihara, T. and Komeya, K. and Meguro, T.
Kuei Suan Jen Hsueh Pao/ Journal of the Chinese Ceramic Society 34 ( 6 ) 662 - 666 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Control of shrinkage during sintering of alumina ceramics based on Master Sintering Curve theory
Tatami, J. and Suzuki, Y. and Wakihara, T. and Meguro, T. and Komeya, K.
Key Engineering Materials 317-318 11 - 14 2006
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of high purity β-SiAlON nanopowder from a zeolite by gas-reduction-nitridation
Yamakawa, T. and Wakihara, T. and Tatami, J. and Komeya, K. and Meguro, T.
Ceramic Transactions 190 3 - 8 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of AlN powder from Al(OH)(3) by reduction-nitridation in a mixture of NH3-C3H8 gas
Yamakawa, T and Tatami, J and Komeya, K and Meguro, T
Journal of the European Ceramic Society 26 ( 12 ) 2413 - 2418 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Temperature dependence of the electrical properties and seebeck coefficient of AlN-SiC ceramics
Kobayashi, R and Tatami, J and Wakihara, T and Meguro, T and Komeya, K
Journal of the American Ceramic Society 89 ( 4 ) 1295 - 1299 2006 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Abe H, Sato K, Naito M, Nogi K, Hotta T, Tatami J, Komeya K
POWDER TECHNOLOGY 159 ( 3 ) 155 - 160 2005.11 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Electrically conductive CNT-dispersed silicon nitride ceramics
Tatami J, Katashima T, Komeya K, Meguro T, Wakihara T
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 88 ( 10 ) 2889 - 2893 2005.10 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p> <jats:bold>Carbon nanotube (CNT)‐dispersed Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics with electrical conductivity were developed based on the lower temperature densification technique, in which the key point is the addition of both TiO<jats:sub>2</jats:sub> and AlN as well as Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> as sintering aids. This new ceramic with a small amount of CNTs exhibits very high electrical conductivity in addition to high strength and toughness. Since Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics with Y<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–TiO<jats:sub>2</jats:sub>–AlN were originally used as a wear material, electrically conductive Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> ceramics are expected to be applied for high‐performance static‐electricity‐free bearings for aerospace and other high‐performance components.</jats:bold> </jats:p>
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Nanofractography of Alumina by Scanning Probe Microscopy
Junichi Tatami, Tomoko Ohbuchi, Katsutoshi Komeya, Takeshi Meguro
Key Engineering Materials 290 70 - 77 2005.7
Language：English Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications, Ltd. Joint Work
<jats:p>Observation of fracture surfaces in ceramics is useful for improving their mechanical properties. In this study, fracture surfaces of polycrystalline alumina were observed using scanning-probe microscopy (SPM) on a nanoscale, also called “nano-fractography.” The average grain size of polycrystalline alumina specimen used in this study was 4.5µm, and the fracture toughness was 3.0MPa・m-1/2. The fracture mode was found to be a mixture of intergranular and transgranular fractures. The fracture surface of intergranular fractures consisted of smooth and rough areas composed of very small steps, whose detection was impossible using scanning electron microscopy. Cleavage and non-cleavage fractures were observed in transgranular fracture grains. The fracture surface of single-crystalline alumina, which is the typical model of the transgranular fracture, was also observed by SPM. The cleavage plane of alumina macroscopically exhibited a very smooth, glass-like surface. However, sub-nano meter steps can be observed on the cleavage fracture surface and appear to be formed by plastic deformation during crack propagation because the size of the step nears that of the Burgers vector.</jats:p>
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Nanofractography of alumina by scanning probe microscopy
Key Engineering Materials 290 70 - 77 2005.6
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Effect of Granule Compaction Procedures of Aluminum Nitride on the Properties of Green Body and Resultant Ceramics
Journal of the Society of Powder Technology 42 ( 4 ) 238 - 243 2005.4 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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Effect of Processing Conditions on the microstructure and properties of AlN ceramics
SATO Kazuyoshi, ABE Hiroya, NAITO Makio, NOGI Kiyoshi, HOTTA Tadashi, TATAMI Junichi
31 ( 1 ) 14 2005.1 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10029252802
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Nanofractography of alumina by scanning probe microscopy
Tatami J, Ohbuchi T, Komeya K, Meguro T
FRACTOGRAPHY OF ADVANCED CERAMICS II 290 70 - 77 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Electrical proparties of sintered body composed of Mn-Co-Ni spinel-type oxides
Abe Yoshiaki, Meguro Takeshi, Yokoyama Takashi, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 157 - 157 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974784
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Development of electrically conductive CNT-Si3N4 composites
Tatami Junichi, Katashima Tomofumi, Komeya Katsutoshi, Wakihara Toru, Meguro Takeshi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2005 ( 0 ) 636 - 636 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
In this study, we developed electrical conductive Si3N4 ceramics using the novel sintering aid, which we found out not only that it enabled Si3N4 to be densified at lower temperature but also that it resulted in excellent mechanical and tribological properties. Although it is difficult to obtain dense sintered body in the CNT dispersed Si3N4-Y2O3-Al2O3 system because of interruption of densification by CNT, dense Si3N4 ceramics could be fabricated at lower temperature occurred in our novel sintering aids in spite of CNT addition. As a result of SEM observation, CNT can be confirmed to be surviving in the Si3N4 ceramics. Crystalline phases of Si3N4 ceramics with novel sintering aids, and small amount of CNT were the same as that without CNT. On the other hand, when only Y2O3 and Al2O3 addition were used as sintering aids or the large amount of CNT was added, SiC was identified by XRD analysis, which probably resulted from the reaction between SiO2, CNT and N2, or Si3N4 and CNT. Since such reaction with gas formation is difficult to be advanced in a closed pore, CNT remained in the Si3N4 ceramics fabricated using the novel sintering aid. Furthermore, in the case of the large amount of CNT addition, α-SiAlON was also formed because of the change in the liquid phase. Electrical conductivity of CNT dispersed Si3N4 ceramics was over 10S/m. Consequently, it was shown that the electrical conductive Si3N4 ceramics could be developed by lower temperature densification technique.
Other Link： https://ci.nii.ac.jp/naid/130006971863
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sakaguchi yoshikazu, tatami junichi, wakihara toru, komeya katutoshi, meguro takeshi, kuibira akira … Show more authors
sakaguchi yoshikazu, tatami junichi, wakihara toru, komeya katutoshi, meguro takeshi, kuibira akira, nakata hirohiko Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 559 - 559 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972319
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Effects of process parameters on post reaction sintering of silicon nitride ceramics
wakihara toru, tatami junichi, komeya katsutoshi, meguro takeshi, kita hideki, kondo naoki
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 842 - 842 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972750
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Evaluation of nano-fractography of single-crystal alumina by scanning probe microscopy
Ohbuchi Tomoko, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 183 - 183 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974313
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Abe Hiroya, Sato Kazuyoshi, Naito Makio, Nogi Kiyoshi, Hotta Tadashi, Tatami Junichi
Journal of the Society of Powder Technology, Japan 42 ( 4 ) 238 - 243 2005 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：The Society of Powder Technology, Japan Joint Work
The effect of granule compaction procedures of aluminum nitride on the properties of green body and the resultant ceramics were examined. Aluminun nitride granules were uniaxially pressed, and then three kinds of pressing procedures were applied. As a result, the fracture strength of sintered body was changed depending on CIP and dewaxing procedures. Higher pressure of CIP resulted in higher fracture strength of ceramics. However, the fracture toughness and thermal conductivity of ceramics did not change with the compaction procedures as long as the microstructure and density of ceramics were the same. The difference in fracture strength was caused by the size of defects in the sintered body, which was observed through the thinned specimen in transmission mode of optical microscope. The defect size changed with the CIP/dewaxing procedures as well as the pressure of CIP. Since the dewaxed granules had higher compressive strength than the waxed granules, the larger defects within the ceramics occurred when the dewaxing of green body was conducted prior to CIP.
Other Link： https://ci.nii.ac.jp/naid/130003952702
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hirasaki tetsuro, meguro takeshi, tatami juniti, komeya katutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 321 - 321 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971459
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Fabrication and evaluation of transparent SiO<sub>2</sub> glass sintered body through floc-casting
HIRATSUKA Daisuke, TATAMI Junichi, WAKIHARA Toru, KOMEYA KatsuToshi, MEGURO Takeshi, IBUKIYAMA Masa … Show more authors
HIRATSUKA Daisuke, TATAMI Junichi, WAKIHARA Toru, KOMEYA KatsuToshi, MEGURO Takeshi, IBUKIYAMA Masahiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 546 - 546 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972667
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Synthesis of Beta-SiAlONs using Zeolite by Gas Reduction Nitridation
Yamakawa Tomohiro, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 50 - 50 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974910
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Synthesis of alpha-SiAlONs using Zeolite
Wakihara Toru, Kamiwaki Satoshi, Yamakawa Tomohiro, Tatami Junichi, Komeya Katsutoshi, Meguro Takes … Show more authors
Wakihara Toru, Kamiwaki Satoshi, Yamakawa Tomohiro, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 49 - 49 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974757
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Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komaya Katsutoshi, Meguro Takeshi, Kenneth J.D.Ma … Show more authors
Yamakawa Tomohiro, Tatami Junichi, Wakihara Toru, Komaya Katsutoshi, Meguro Takeshi, Kenneth J.D.MacKenzie, Takagi Shinichi, Yokouchi Masahiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 812 - 812 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973187
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Synthesis of Nitride Ceramics by Gas-reduction Nitridation - Synthesis of SiAlON from Zeolite -
Yamakawa Tomohiro, Wakihara Toru, Tatami Junichi, Komaya Katsutoshi, Meguro Takeshi, Kenneth J.D.Ma … Show more authors
Yamakawa Tomohiro, Wakihara Toru, Tatami Junichi, Komaya Katsutoshi, Meguro Takeshi, Kenneth J.D.MacKenzie, Takagi Shinichi, Yokouchi Masahiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 813 - 813 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973186
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Yoshida Yusuke, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Yokouchi Masahiro … Show more authors
Yoshida Yusuke, Wakihara Toru, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Yokouchi Masahiro, Takagi Shinichi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 809 - 809 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006973191
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Kumasawa Satoshi, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 327 - 327 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971457
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Yoshida Yusuke, Wakihara Toru, Tatami Junichi, Komeya Katutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 322 - 322 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006971447
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Influence of a-content of raw materials on sinterability and microstructure of Si3N4-Y2O3-MgO system
kumazawa satoshi, tatami juniti, meguro takeshi, komeya katsutoshi, ibukiyama masahiro
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2005 ( 0 ) 841 - 841 2005
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006972751
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Characteristics of dehumidifier sheets for an adsorptive desiccant cooling system
Tashiro Y, Kubo M, Katsumi Y, Meguro T, Komeya K, Tatami J
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS 146 199 - 205 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of AIN by gas-reduction-nitridation of transition alumina powder
Yamakawa T, Tatami J, Meguro T, Komeya K
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS 146 179 - 186 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Tatami J, Komeya K, Hoshina T, Hirata T, Meguro T, Tsuge A
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS 146 299 - 306 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microstructure of AlN fibers synthesized from Al2O3 by gas-reduction-nitridation
Matsumoto Y, Tatami J, Meguro T, Komeya K, Yano T
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS 146 291 - 297 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microstructure and mechanical properties of AlN ceramics with Y2O3
Iwasawa S, Tatami J, Komeya K, Meguro T
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS 146 285 - 290 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effects of alpha phase content on the sintering behavior of Si3N4 powder
Nishimizu R, Tatami J, Komeya K, Meguro T, Ibukiyama M
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS 146 187 - 192 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Contact damage behavior of TiN-coated Si3N4 ceramics
Suzuki S, Tatami J, Komeya K, Meguro T, Azushima AS, Kim YG, Kim DK
CHARACTERIZATION AND CONTROL OF INTERFACES FOR HIGH QUALITY ADVANCED MATERIALS 146 409 - 415 2005
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Nanofractography of alumina by scanning probe microscopy
Tatami, J. and Ohbuchi, T. and Komeya, K. and Meguro, T.
Key Engineering Materials 290 70 - 77 2005
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications Ltd. Joint Work
<jats:p>Observation of fracture surfaces in ceramics is useful for improving their mechanical properties. In this study, fracture surfaces of polycrystalline alumina were observed using scanning-probe microscopy (SPM) on a nanoscale, also called “nano-fractography.” The average grain size of polycrystalline alumina specimen used in this study was 4.5µm, and the fracture toughness was 3.0MPa・m-1/2. The fracture mode was found to be a mixture of intergranular and transgranular fractures. The fracture surface of intergranular fractures consisted of smooth and rough areas composed of very small steps, whose detection was impossible using scanning electron microscopy. Cleavage and non-cleavage fractures were observed in transgranular fracture grains. The fracture surface of single-crystalline alumina, which is the typical model of the transgranular fracture, was also observed by SPM. The cleavage plane of alumina macroscopically exhibited a very smooth, glass-like surface. However, sub-nano meter steps can be observed on the cleavage fracture surface and appear to be formed by plastic deformation during crack propagation because the size of the step nears that of the Burgers vector.</jats:p>
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Nanofractography of alumina by scanning probe microscopy
Tatami, J and Ohbuchi, T and Komeya, K and Meguro, T and Dusza, J and Danzer, R and Morrell, R
Fractography of Advanced Ceramics Ii 290 70 - 77 2005
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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カーボンナノチューブ添加による高機能セラミックスの開発--摺動部材としての導電性窒化ケイ素
米屋 勝利, 多々見 純一
粉砕 = The micromeritics ( 49 ) 31 - 37 2005 [Reviewed]
Authorship：Last author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ホソカワ粉体技術研究所 Joint Work
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Determining grain size in ceramics
Hotta T, Tatami J, Tanaka H, Shinohara N, Emoto H, Hattori M, Kishi Y, Abe H, Naito M, Uematsu K
AMERICAN CERAMIC SOCIETY BULLETIN 83 ( 11 ) 9101 - 9105 2004.11
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effect of Coarser Grains in Raw Powder on Inhomogeneous Structure in AlN Sintered Body
NAKATA Hirohiko, TATAMI Junichi, NAMIKI Masahiro, KOMEYA Katsutoshi, MEGURO Takeshi, KUIBIRA Akira, … Show more authors
NAKATA Hirohiko, TATAMI Junichi, NAMIKI Masahiro, KOMEYA Katsutoshi, MEGURO Takeshi, KUIBIRA Akira, NAITO Makio, HOTTA Tadashi Hide authors
Journal of the Ceramic Society of Japan 112 ( 1301 ) 35 - 39 2004.1 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Development of Ca-αSiAlON nano ceramics by spark plasma sintering
Proceedings of 2nd MP3 2004
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Corrosion resistance of Ca-α SiAlON nano ceramics
Proceedings of 2nd MP3 2004
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of AlN powder by firing transition alumina in NH3-C3H8 mixed gas
Proceedings of 2nd MP3 191 - 200 2004
Language：English Publishing type：Research paper (international conference proceedings)
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Determining Grain Size in Ceramics
Am.Ceram.Soc.Bull. 83 ( 11 ) 9101 - 9105 2004 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microstructure and Properties of AlN-SiC ceramics
Kobayashi Ryota, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 504 - 504 2004
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974487
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Abe Yoshiaki, Nimura Atushi, Sato Satoshi, Yokoyama Takashi, Meguro Takeshi, Komeya Katsutoshi, Tat … Show more authors
Abe Yoshiaki, Nimura Atushi, Sato Satoshi, Yokoyama Takashi, Meguro Takeshi, Komeya Katsutoshi, Tatami Junichi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 352 - 352 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Changes in crystal phase and electric resistance of a Mn-Co-Ni (2.5:1.0:2.5) oxide sintered at 1200C during heat treatment were investigated. When fired at 1200C, two kinds of crystals, tetragonal spinel and rock salt type oxides, coexisted in the specimen. The specimen heat-treated at 1000C for 1h had three kinds of crystal, cubic and tetragonal spinels and rock salt type oxides. In the specimen heat-treated for more than 3h, the crystal was composed of cubic spinel and rock salt type oxides. The electrical properties were found to depend on the cubic spinel oxide.
Other Link： https://ci.nii.ac.jp/naid/130006967028
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Suzuki Yusuke, Tatami Juniti, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 186 - 186 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006969663
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Tatami Junichi, Nishimizu Ryouichi, Wakihara Tohru, Komeya Katsutoshi, Meguro Takeshi, Ibukiyama Ma … Show more authors
Tatami Junichi, Nishimizu Ryouichi, Wakihara Tohru, Komeya Katsutoshi, Meguro Takeshi, Ibukiyama Masahiro Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 185 - 185 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006969660
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Okada Shigefumi, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 184 - 184 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006969661
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Formation Process and α-β Transformation of SiAlON prepared from Minerals
QIU Jin-Yu, TATAMI Junichi, KOMEYA Katsutoshi, WATARI Koji, MEGURO Takeshi
Journal of the Ceramic Society of Japan, Supplement 112 ( 0 ) 2004 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人 日本セラミックス協会 Joint Work
This paper investigated the preparation of Mg-α SiAlON ceramic from mixtures of talc (Mg<sub>3</sub>(Si<sub>2</sub>O<sub>5</sub>)<sub>2</sub>(OH)<sub>2</sub>) and halloysite clay (Al<sub>2</sub>Si<sub>2</sub>O<sub>5</sub>(OH)<sub>4</sub>). Firstly, Carbothermal Reduction-Nitridation (CRN) of these raw materials mixtures was used to synthesize Mg-α SiAlON powders. Subsequently, densification of Mg-α SiAlON ceramic using these as-synthesized powders was attempted through gas pressure sintering (GPS) method. The effects of sintering additive on the density and phases of sintered bodies were investigated. As a result, in the case of without sintering additive, phase transformation to β-SiAlON was enhanced with elevating temperatures. In contrast, the sample doped with α-Si<sub>3</sub>N<sub>4</sub> was fully densified after sintering at 1950°C for 2 h and a main phase was α-SiAlON. The sintered density of Mg-α SiAlON ceramics composed of fine and uniform grains was higher than 3.10 g/cm<sup>3</sup>, hardness was above 1700 MPa, and fracture toughness (K<sub>IC</sub>) reached 4.6 MPam<sup>1/2</sup>.
Other Link： https://ci.nii.ac.jp/naid/130004610039
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Synthesis of dual-cation alpha-sialon powders containing calcium and cerium or europium
Hotta Mikinori, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Enomoto Naoya, Hojo Junichi, Che … Show more authors
Hotta Mikinori, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Enomoto Naoya, Hojo Junichi, Cheng Yi-Bing Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 479 - 479 2004
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006969199
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Microstructural Characteizaton and properties of AlN Ceramics with Tb4O7
Iwasawa Seiji, Tatami Juniti, Meguro Takeshi, Komeya Katutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 167 - 167 2004
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006967855
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Analysis of fracture behavior in Al<sub>2</sub>O<sub>3</sub> by SPM
OHBUCHI Tomoko, TATAMI Junichi, MEGURO Takeshi, KOMEYA Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 485 - 485 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974801
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Fabrication of corrosive resistant b-SiAlON Nano ceramics
HIRATSUKA Daisuke, TATAMI Junichi, MEGURO Takeshi, KOMEYA Katsutoshi, HAYASHI ICHIRO, YAN J-Feng, O … Show more authors
HIRATSUKA Daisuke, TATAMI Junichi, MEGURO Takeshi, KOMEYA Katsutoshi, HAYASHI ICHIRO, YAN J-Feng, OHMORI Mamoru, Li Q Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 162 - 162 2004
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
b-SiAlON nano ceramics were fabricated by spark plasma sintering using the ultra fine powder synthesized through carbothermal reduction-nitrogen method, and its aqueous and gas corrosion resistance were evaluated. As a result of TEM observation,the devoloped b-SiAlON ceramics were composed of nano-sized grains and the glassy phase was hardly found at the grain boundary. It showed much higher aqueous corrosion resistance than commercialized Si3N4 ceramics. We also obtained valuable information of corrosion surface from SPM observation.Furthermore, the b-SiAlON nano ceramics possessed high corrosion resistance to air and air-SOXgas mixture at high temperature. It is considered excellent thermal and chemical durability of b-SiAlON but also very little glassy phase in their grain boundary.
Other Link： https://ci.nii.ac.jp/naid/130006967791
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Evaluation of nano-fractography of alumina by scanning probe microscopy
Ohbuchi Tomoko, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 361 - 361 2004
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006967263
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Analysis of sintering behavior of Si<sub>3</sub>N<sub>4</sub>
Tatami Junichi, Nishimizu Ryouichi, Toyama Masaki, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 159 - 159 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006967785
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HOTTA Mikinori, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi, CHENG Yi-Bing, ENOMOTO Naoya, HO … Show more authors
HOTTA Mikinori, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi, CHENG Yi-Bing, ENOMOTO Naoya, HOJO Junichi Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 156 - 156 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006967786
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Corrosion Resistance of Reaction-Sintered Silicon Carbide
Kinoshita Ayako, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi, Suyama Syouko, Kameda Tsuneji, … Show more authors
Kinoshita Ayako, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi, Suyama Syouko, Kameda Tsuneji, Yano Toyohiko Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 501 - 501 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006974493
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Synthesis of AlN nano-particle by Gas-reduction-nitridation
Yamakawa Tomohiro, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 165 - 165 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006967853
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Yamakawa Tomohiro, Wakihara Toru, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi, Kenneth MacKen … Show more authors
Yamakawa Tomohiro, Wakihara Toru, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi, Kenneth MacKenzie Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 490 - 490 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006969207
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Tribological properties of Si<sub>3</sub>N<sub>4</sub>-TiN composites
Watanabe Hiroshi, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi, Komatsu Michiyasu, Azushima Ak … Show more authors
Watanabe Hiroshi, Tatami Junichi, Meguro Takeshi, Komeya Katsutoshi, Komatsu Michiyasu, Azushima Akira Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 163 - 163 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006967789
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Watanabe Hiroshi, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi, Komatsu Michiya … Show more authors
Watanabe Hiroshi, Tatami Junichi, Wakihara Toru, Meguro Takeshi, Komeya Katsutoshi, Komatsu Michiyasu, Azushima Akira Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2004 ( 0 ) 370 - 370 2004 [Reviewed]
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/130006969697
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Determining grain size in ceramics
Hotta, T. and Tatami, J. and Tanaka, H. and Shinohara, N. and Emoto, H. and Hattori, M. and Kishi, … Show more authors
Hotta, T. and Tatami, J. and Tanaka, H. and Shinohara, N. and Emoto, H. and Hattori, M. and Kishi, Y. and Abe, H. and Naito, M. and Uematsu, K. Hide authors
American Ceramic Society Bulletin 83 ( 11 ) 2004
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Determining grain size in ceramics
Hotta, T and Tatami, J and Tanaka, H and Shinohara, N and Emoto, H and Hattori, M and Kishi, … Show more authors
Hotta, T and Tatami, J and Tanaka, H and Shinohara, N and Emoto, H and Hattori, M and Kishi, Y and Abe, H and Naito, M and Uematsu, K Hide authors
American Ceramic Society Bulletin 83 ( 11 ) 9101 - 9105 2004
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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An improvement of thermal conduction of activated carbon by adding graphite
Kuwagaki H, Meguro T, Tatami J, Komeya K, Tamura K
JOURNAL OF MATERIALS SCIENCE 38 ( 15 ) 3279 - 3284 2003.8 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Corrosion of High Thermal Conductive AlN Ceramics in Aqueous Solutions
TATAMI Junichi, LIN Chin-Ho, MEGURO Takeshi, KOMEYA Katsutoshi, ABE Yutaka, KOMATSU Michiyasu, OKAM … Show more authors
TATAMI Junichi, LIN Chin-Ho, MEGURO Takeshi, KOMEYA Katsutoshi, ABE Yutaka, KOMATSU Michiyasu, OKAMOTO Mitsuhiro Hide authors
Journal of the Ceramic Society of Japan 111 ( 8 ) 604 - 607 2003.8 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Fabrication of β-SiAlON Nano-Ceramics and their Properties
Q. Li, Katsutoshi Komeya, Junichi Tatami, Takeshi Meguro, L. Gao
Key Engineering Materials 247 75 - 78 2003.8
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
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Corrosion Resistance of Wear Resistant Silicon Nitride Ceramics in Various Aqueous Solutions
LIN Chin-Ho, KOMEYA Katsutoshi, MEGURO Takeshi, ABE Yutaka, TATAMI Junichi, KOMATSU Michiyasu
Journal of the Ceramic Society of Japan 111 ( 7 ) 452 - 456 2003.7 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Nano powders of beta-sialon carbothermally produced via a sol-gel process
Li Q, Zhang C, Komeya K, Tatami J, Meguro T, Gao L
JOURNAL OF MATERIALS SCIENCE LETTERS 22 ( 12 ) 885 - 887 2003.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of aluminum nitride nanopowder by gas-reduction-nitridation method
Suehiro T, Hirosaki N, Terao R, Tatami J, Meguro T, Komeya K
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 86 ( 6 ) 1046 - 1048 2003.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of Aluminum Nitride Nanopowder by Gas‐Reduction–Nitridation Method
Takayuki Suehiro, Naoto Hirosaki, Ryo Terao, Junichi Tatami, Takeshi Meguro, Katsutoshi Komeya
Journal of the American Ceramic Society 86 ( 6 ) 1046 - 1048 2003.6
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>Aluminum nitride (AlN) nanopowder was successfully synthesized from transition alumina nanopowder using an NH<jats:sub>3</jats:sub>–C<jats:sub>3</jats:sub>H<jats:sub>8</jats:sub> gas mixture as a reduction–nitridation agent. Phase‐pure, nanocrystalline AlN powder with a specific surface area of 36.4 m<jats:sup>2</jats:sup>/g and a mean particle size of 51 nm was prepared under typical reaction conditions. The resulting AlN nanopowders possessed excellent sinterability, allowing full densification in conventional processing, even without the addition of sintering aids.</jats:p>
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Trends of Research and Development of Engineering Ceramics
NIIHARA Koichi, TATAMI Junichi
Ceramics Japan 38 ( 4 ) 301 - 303 2003.4
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/80015854686
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Synthesis of Ca-α SiAlON Hollow Balls
Mikinori Hotta, Junichi Tatami, Takeshi Meguro, Yi-Bing Cheng, Katsutoshi Komeya, C. Zhang
Key Engineering Materials 237 87 - 94 2003.4 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
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技術解説/新製品・新技術 耐摩耗材料としての窒化ケイ素系材料
米屋 勝利, 多々見 純一
Fine ceramics report 21 ( 2 ) 32 - 38 2003.2
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本ファインセラミックス協会 Joint Work
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Fabrication and Evaluation of Porous Ca-α SiAlON Ceramics
Ceramics Transaction 142 77 - 87 2003
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Fabrication of β-Sialon Nano-Ceramics and their Properties
Key Engineering Materials 247 75 - 78 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Effect of TiO2 and AlN Additions on the Sintering Behavior of the Si3N4-Y2O3-Al2O3 Sysytem
Key Engineering Materials 247 83 - 86 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Effect of Coarser Grains on Sintering of AlN
Key Engineering Materials 247 87 - 90 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and Evaluation of Reaction-Bonded Aluminium Nitride from Al Powder Compacts Coated with CaCO3, SrCO3 and BaCO3
Key Engineering Materials 247 105 - 108 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of β-Sialon Powder by Carbothermal Reduction-Nitridation of Zeolite
Key Engineering Materials 247 109 - 112 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Densification of Ca-α Sialon Nano Particles by Spark Plasma Sintering
Key Engineering Materials 247 71 - 74 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of Ca-α Sialon, Key Engineering Materials
Key Engineering Materials 237 87 - 94 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and Evaluation of Ca-α Sialon Nano Ceramics
Key Engineering Materials 237 105 - 110 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Nano β-Sialon Powder Synthesized by Carbothermal Reduction-Nitridation of Ultrafine Al2O3-SiO2 Mixture Employing Sol-Gel Techniques
Key Engineering Materials 237 1117 - 1122 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Appications of Electric Double Layer Formed by Large Sueface Areas of Carbons Activated by KOH
KUWAGAKI Hitoshi, MEGURO Takeshi, HIRASAKI Tetsuro, KOMEYA Katsutoshi, TATAMI Junichi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 1101 - 1101 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Ion-storage based on Electric Double Layer(EDL) is brought by polarization at Helm holtz layer under low voltages less than 1 V. Since the bound ions are released when the electrode was discharged or the polarity is reversed, the EDL is expected to an application for removal or concentration of injurious ions from aqueous solution. Furthermore, EDL capacitor can be a candidate of long-life secondary battery. Porous carbons are recognized to be the most suitable material for EDL electrode in that they have large surface areas and their pore size distributions are significantly wide.We have investigated the validity of the high surface areas of carbons prepared by KOH activation. The pore width ranging from 0.5 to 3 nm, which was analyzed by Density Functional Theory, showed to be effective for ion removal and EDL capacitor.
Other Link： https://ci.nii.ac.jp/naid/130006969414
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HISAYASU Takeshi, YOKOYAMA Takashi, ABE Yoshiaki, MEGURO Takeshi, KOMEYA Katsutoshi, TATAMI Junichi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 469 - 469 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Preparation of spinel-type oxides, Mn<SUB>(1.5-0.25X)</SUB>CoNi<SUB>(0.5+0.25X)</SUB>O<SUB>4</SUB>(0≤X≤1),and their electrical properties were investigated. Starting oxides, containing metals with desired molar ratios, were heated to 1400<SUP>o</SUP>C and held for 3h in argon. The sintered specimens which were composed of rock salt structure were cooled to 800<SUP>o</SUP>C and then oxidized for 48h in air to be converted into cubic spinel structure in all range of X. The electrical conductivity of the sintered bodies was confirmed to increase exponentially with increasing temperature. The Seebeck coefficients decreased with increasing X. The oxides, in the region of 0≤X≤0.46, are considered to be p-type semiconductors and the others n-type semiconductors. The electrical conduction of the oxides was considered to be controlled by a small polaron hopping mechanism.
Other Link： https://ci.nii.ac.jp/naid/130006967732
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KUWAGAKI Hitoshi, MEGURO Takeshi, PONDEVIDA Josie L, KOMEYA Katsutoshi, TATAMI Junichi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 1082 - 1082 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Pili (Canarium ovatum) are expectable crop instead of monopolistic plantation of coconut palm in the Philippines. The shells are also usable as a raw material for the production of activated carbon. However, there are few studies on carbonization and activation of Pili shells because of high volatile matter and low fixed carbon contents compared with coconut shells. We have improved the carbonization condition through introducing a process of pre-treatment with H3PO4. Ordinal activation using water vapor was conducted. Consequently, highly developed porous activated carbon could be obtained with high yield. The micro pore size distributions (PSD) were analyzed by the Density Functional Theory. The PSD was found to be controlled by the H3PO4-treatment conditions.
Other Link： https://ci.nii.ac.jp/naid/130006969463
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Li Q, Zhang C, Komeya K, Tatami J, Meguro T, Gao L
SIAIONS 237 117 - 121 2003
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
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Fabrication of Porous Ca-α SiAlON Ceramics
TASAKA Yuuki, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi, OMORI Mamoru
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 738 - 738 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
We have reported that Ca-α sialon hollow ball with 200-500nm in diameter which is composed of very fine particles with 10-30nm in diameter could be synthesized by carbothermal reduction-nitridation method. In this study, the porous Ca-α sialon was produced from the Ca-α sialon hollow through the spark plasma sintering (SPS) method. SPS was carried out at the temperature of 1650 to 1700<SUP>0</SUP>C for 1 min in 0.1MPaN<SUB>2</SUB>under uniaxial pressing at 5MPa. It was confirmed that the porous Ca-α sialon ceramics was obtained. The shape of hollow ball remained after sintering to have bimodal pore size distribution which corresponded to the size of hollow balls and the space between primary grains.The strength of the porous material was found to be higher than conventional porous alumina ceramics with the same porosity.
Other Link： https://ci.nii.ac.jp/naid/130006969028
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Fabrication of Porous AlN Ceramics Utilizing Plate-like Grain Structure of AlN Polytypoid
FURUKAWA Yuuko, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 740 - 740 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Porous AlN ceramics were fabricated from the porous AlN polytypoid ceramics by elimination of Si and O through carbonthermal reduction-nitiridation at high temperature. The powder compacts of AlN and SiO<SUB>2</SUB> were fired at 1900°C for 6h in a Si<SUB>3</SUB>N<SUB>4</SUB> crucible and then the sintered bodies were heat-treated at 1800 and 1900°C for 0 to 3h in a carbon crucible.As-sintered specimens were mainly composed of 27R or 21R AlN polytypoids. After heat treatment, plate-like grain structure of AlN polytypoids was mostly maintained after heat treatment. The maintenance of morphology probably resulted from structural similarity between AlN polytypoids and AlN, such as psuedomorph in several kinds of minerals. The porosity of the porous AlN ceramics was about 50% and its pore size distribution was narrow. It has low dielectric constant and high thermal conductivity.
Other Link： https://ci.nii.ac.jp/naid/130006969031
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Fabrication of beta-SiAlON nano-ceramics and their properties
Li Q, Komeya K, Tatami J, Meguro T, Gao L
ADVANCED CERAMICS AND COMPOSITES 247 75 - 78 2003
Authorship：Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluatton of porous ca-alpha SiAlON ceramics
Tatami J, Ohta T, Hang C, Hotta M, Komeya K, Meguro T, Omori M, Hirai T
SILICON-BASED STRUCTURAL CERAMICS FOR THE NEW MILLENNIUM 142 77 - 87 2003
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Wakamatsu T, Tatami J, Komeya K, Meguro T
ADVANCED CERAMICS AND COMPOSITES 247 105 - 108 2003
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications, Ltd. Joint Work
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Fabrication and evaluation of Ca-alpha SiAlON nano ceramics
Tatami J, Iguchi M, Hotta M, Zhang C, Komeya K, Meguro T, Omori M, Hirai T, Brito ME, Cheng YB
SIAIONS 237 105 - 110 2003
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
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Abe Y, Meguro T, Yokoyama T, Morita T, Tatami J, Komeya K
JOURNAL OF CERAMIC PROCESSING RESEARCH 4 ( 3 ) 140 - 144 2003 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effect of TiO2 and AlN additions on the sintering behavior of the Si3N4-Y2O3-Al2O3 system
Tatami J, Toyama M, Noguchi K, Komeya K, Meguro T, Komatsu M
ADVANCED CERAMICS AND COMPOSITES 247 83 - 86 2003
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications, Ltd. Joint Work
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Effect of Sintering Aids on Sintering of Mg-α SiAlON Powder
QIU Jin-Yu, KOMEYA Katsutoshi, WATARI Koji, TATAMI Junichi, MEGURO Takeshi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 818 - 818 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Using Mg-α SiAlON powder synthesized by carbothermal reduction-nitridation, fabrication of Mg-α SiAlON ceramics was attempted through gas pressure sintering method. The effects of firing temperatures and sintering aids on the density and phases of sintered bodies were investigated. As a result, in the case of no addition of sintering aid, phase transformation to β-SiAlON was enhanced with elevating temperatures. Furthermore, it was found that dense Mg-α SiAlON sintered body could be obtained by addition of α-Si<SUB>3</SUB>N<SUB>4</SUB>, whereas β-SiAlON, SiC, 15R and AlN, which existed in as-synthesized powders, completely diminished after high temperature firing. The dense Mg-α SiAlON ceramics composed of fine and uniform grains could be obtained with 5wt% α-Si<SUB>3</SUB>N<SUB>4</SUB> additive through firing at the temperature of 1950°C for 2 hours.
Other Link： https://ci.nii.ac.jp/naid/130006969040
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Effect of coarser grains on sintering of AlN
Hoshina T, Tatami J, Meguro T, Komeya K, Tsuge A, Kuibira A, Nakata H
ADVANCED CERAMICS AND COMPOSITES 247 87 - 90 2003
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications, Ltd. Joint Work
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Densification of Ca-alpha SiAlON nano particles by spark plasma
Iguchi M, Tatami J, Hotta M, Zhang C, Komeya K, Meguro T, Omori M, Hirai T, Brito ME, Cheng YB
ADVANCED CERAMICS AND COMPOSITES 247 71 - 74 2003
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：Trans Tech Publications, Ltd. Joint Work
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Corrosion Resistance of Porous AlN Polytypoid in Aqueous Solution
KONNO Wataru, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 739 - 739 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
There are many types of polytypoids with layered crystal structure in the vicinity of AlN in the phase diagram of the system Si<SUB>3</SUB>N<SUB>4</SUB>-Al<SUB>2</SUB>O<SUB>3</SUB>-AlN-SiO<SUB>2</SUB>. We have developed porous AlN polytypoid ceramics with plate-like grain structure based on its anisotropy by firing a powder compact of AlN-SiO<SUB>2</SUB> at 1900°C for 6h in a Si<SUB>3</SUB>N<SUB>4</SUB>crucible. Corrosion behavior of AlN polytypoid with 10mass% SiO<SUB>2</SUB>addition was examined in H<SUB>2</SUB>SO<SUB>4</SUB> solution and ion-exchange water. Weight changes per surface area, phases present and microstructures before and after testing were evaluated. Sintered specimens were mainly composed of 27R AlN polytypoids and their relative density was about 50%. The weight changes were found to be much smaller than commercialized AlN ceramics. Although pore size distributions were slightly changed, phases present and microstructures after corrosion test were almost the same as those before test. Consequently, it was shown that AlN polytypoid had excellent corrosion resistance.
Other Link： https://ci.nii.ac.jp/naid/130006969029
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Corrosion Resistance of β-SiAlON Nano Ceramics
TATAMI Junichi, NAGATOME Azuma, LI Qiang, KOMEYA Katsutoshi, MEGURO Takeshi, HAYASHI Ichiro, YAN Ji … Show more authors
TATAMI Junichi, NAGATOME Azuma, LI Qiang, KOMEYA Katsutoshi, MEGURO Takeshi, HAYASHI Ichiro, YAN JianFeng, OMORI Mamoru Hide authors
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 737 - 737 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
β-SiAlON nano ceramics were fabricated by spark plasma sintering using the ultra fine powder synthesized through carbothermal reduction-nitridation method, and its aqueous and gas corrosion resistance were evaluated. As a result of TEM observation,the developed β-SiAlON ceramics were composed of nano-sized grains and the glassy phase was hardly found at the grain boundary. It showed much higher aqueous corrosion resistance than commercialized Si<SUB>3</SUB>N<SUB>4</SUB>ceramics. Furthermore, the βSiAlON nano ceramics possessed high corrosion resistance to air and air-SO<SUB>x</SUB>gas mixture at high temperature. It is considered that the improvement of these properties resulted from not only excellent thermal and chemical durability of βSiAlON but also very little glassy phase in their grain boundary.
Other Link： https://ci.nii.ac.jp/naid/130006969024
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Corrosion of highly thermal conductive AlN ceramics in aqueous solutions
Lin CH, Tatami J, Meguro T, Komeya K, Abe Y, Komatsu M, Okamoto M
ADVANCED CERAMICS AND COMPOSITES 247 235 - 238 2003
Authorship：Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Silicon Nitride Ceramics Strengthened by In-Situ Precipitation of TiN
KOMEYA Katsutoshi, TATAMI Junichi, MEGURO Takeshi, KOMATSU Mitiyasu, YANO Toyohiko
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 690 - 690 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Si<SUB>3</SUB>N<SUB>4</SUB> is one of the mostattractive materials for wear applications. Some of the authors have beeninvolved in the creation and development of this material as a pioneer researcher. At present, a high-quality Si<SUB>3</SUB>N<SUB>4</SUB> ceramic foruse as wear components has been fabricated from the system Si<SUB>3</SUB>N<SUB>4</SUB>-Y<SUB>2</SUB>O<SUB>3</SUB>-Al<SUB>2</SUB>O<SUB>3</SUB>-TiO<SUB>2</SUB>-AlN,but the sintering behavior was not clear. Thus we have investigated the effectof adding TiO<SUB>2</SUB> and AlN on the densification and microstructure development in the above system. As a result, we found the TiO<SUB>2</SUB> promoted the densification changing into TiN, which was precipitated betweenthe grain boundary as isotropic grains. Strengthening effect of the dispersion of TiN grains was discussed by microstructural analysis and contact damage testing method.
Other Link： https://ci.nii.ac.jp/naid/130006970132
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HIRASAKI Tetsuro, MEGURO Takeshi, KOMEYA Katsutoshi, TATAMI Junichi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 1098 - 1098 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Glasslike carbons have been used in various fields because they have some excellent characteristics such as extremely low gas-permeability, chemical stability. Although such glasslike carbons are proof against high temperatures, the deterioration due to oxidation in an atmosphere with oxygen potential is unavoidable. However, kinetic studies are insufficient to understand the essential reactivity of glasslike carbons. In general, carbonaceous materials react with such oxidants as oxygen and carbon dioxide at high temperatures. For this reason, in this study we have analyzed the kinetics of a glasslike carbon with carbon dioxide, applying the Langmuir-Hinshelwood equation (R=K<SUB>1</SUB>P<SUB>CO<SUB>2</SUB></SUB>/(1+K<SUB>2</SUB>P<SUB>CO</SUB>+K<SUB>3</SUB>P<SUB>CO<SUB>2</SUB></SUB>)) based on the elementary reactions in the Boudouard reaction. The equilibrium constant implying the oxygen exchange reaction and the activation energy for decomposition of surface oxide are discussed, comparing with data on an artificial graphite.
Other Link： https://ci.nii.ac.jp/naid/130006969405
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Synthesis of Ca-alpha SiAlON hollow balls
Komeya K, Tatami J, Hotta M, Zhang C, Meguro T, Cheng YB
SIAIONS 237 87 - 93 2003
Language：English Publishing type：Research paper (scientific journal) Joint Work
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HOTTA Mikinori, CHENG Yi-Bing, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi, MORINAGA Kenji, M … Show more authors
HOTTA Mikinori, CHENG Yi-Bing, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi, MORINAGA Kenji, MASUDA Hirohisa, UEHARA Masato, ENOMOTO Naoya, HOJO Junichi Hide authors
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 299 - 299 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
Ca-α sialon powders were synthesized via carbothermal reduction-nitridation (CRN) of CaO-Al<SUB>2</SUB>O<SUB>3</SUB>-SiO<SUB>2</SUB> glass powder.Ca-α sialon content of about 80wt%, together with β-sialon and AlN as a minor phase was obtained by firing the product at 1450<SUP>o</SUP>C for 2h in N<SUB>2</SUB> gas.SEM observation showed that the resultant powder had ball-like morphology of less than 5μm.According to XRD analysis, crystalline SiO<SUB>2</SUB>, mullite and Si<SUB>2</SUB>N<SUB>2</SUB>O as an intermediate phase were identified at the initial stage of the CRN reaction.The glass powder composed of coarse particle gradually changed into the spherical particles at 1100<SUP>o</SUP>C.The nitridation reaction proceeded from the surface of the spherical particles to generate Si<SUB>2</SUB>N<SUB>2</SUB>O.It was confirmed that the Ca-α sialon particles obtained from CaO-Al<SUB>2</SUB>O<SUB>3</SUB>-SiO<SUB>2</SUB> glass powder were formed through the same process as CaO-Al<SUB>2</SUB>O<SUB>3</SUB>-SiO<SUB>2</SUB> powder mixture.This result suggests that the Ca-α sialon synthesized by CRN of CaO-Al<SUB>2</SUB>O<SUB>3</SUB>-SiO<SUB>2</SUB> system were formed through Ca-Al-Si-O glass.
Other Link： https://ci.nii.ac.jp/naid/130006968653
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Synthesis of beta-SiAlON powder by carbothermal reduction-nitridation of zeolite
Li FJ, Tatami J, Meguro T, Komeya K
ADVANCED CERAMICS AND COMPOSITES 247 109 - 112 2003
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of AlN Polytypoid through the Exothermic Nitridation of the System Al-AlN-SiO<SUB>2</SUB>
SENEVIRATNA Hathanalage A. S., TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 53 - 53 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
AlN polytypoids composed of Al, Si, O and N can be obtained from the AlN-SiO<SUB>2</SUB>. In general, the polytypoids have been fabricated by firing the powder mixture of AlN and SiO<SUB>2</SUB> in N<SUB>2</SUB> atmosphere. In this study, we proposed a new idea to synthesize the polytypoids using the exothermic reaction appeared during firing the Al-AlN-SiO<SUB>2</SUB> in N<SUB>2</SUB> flow. High purity Al, AlN and SiO<SUB>2</SUB> powders were used as raw materials. Various compositions of powder mixtures to form 27R-polytypoids were fired at 700 and 800<SUP>o</SUP>C in N<SUB>2</SUB> flow. The polytypoids were not synthesized by firing the Al-SiO<SUB>2</SUB>, because the reaction of Al + SiO<SUB>2</SUB>= Al<SUB>2</SUB>O<SUB>3</SUB> + Si was preceded. However, by the addition of AlN to the Al-SiO<SUB>2</SUB>, 27R-polytypoid with very fine particle size below 100nm was successfully synthesized through the exothermic nitridation-reaction, which means AlN particles prevented Al particles from contacting SiO<SUB>2</SUB> particles.
Other Link： https://ci.nii.ac.jp/naid/130006967586
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SPM Study of the Fracture Behavior of Ceramics
TATAMI Junichi, YAMAMOTO Youichi, KATSUTOSHI Komeya, MEGURO Takeshi
日本セラミックス協会 年会・秋季シンポジウム 講演予稿集 2003 ( 0 ) 287 - 287 2003
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 日本セラミックス協会 Joint Work
A crack induced by Vickers indentation were observed using scanning probe microscope. Although a crack propagated straight in soda lime glass, the region near the crack was found to be not smooth but slightly gibbous. This phenomenon probably means that plastic deformation occurred during fracture by local stress field at the crack tip in spite of its brittleness. A crack in Si<SUB>3</SUB>N<SUB>4</SUB> ceramics discontinuously propagated in the grain and grain boundary. The discontinuous region after cracking was not level, namely the grain for crack bridging showed a little concavo-convex. It seems that the deformation of the grain resulted from bridging force. Furthermore, some grain boundaries at the crack tip became hollow, which is probably enbrio of the fracture.
Other Link： https://ci.nii.ac.jp/naid/130006968618
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Li, Q. and Zhang, C. and Komeya, K. and Tatami, J. and Meguro, T. and Gao, L.
Key Engineering Materials 237 117 - 122 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Nano beta-SiAlON powder synthesized by carbothermal reduction and nitridation of ultrafine Al2O3-SiO2 mixture employing sol-gel techniques
Li, Q and Zhang, C and Komeya, K and Tatami, J and Meguro, T and Gao, L and Mitomo, M and Ch … Show more authors
Li, Q and Zhang, C and Komeya, K and Tatami, J and Meguro, T and Gao, L and Mitomo, M and Cheng, YB Hide authors
Siaions 237 117 - 121 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Fabrication of β-SiAlON nano-ceramics and their properties
Li, Q. and Komeya, K. and Tatami, J. and Meguro, T. and Gao, L.
Key Engineering Materials 247 75 - 78 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication of beta-SiAlON nano-ceramics and their properties
Li, Q and Komeya, K and Tatami, J and Meguro, T and Gao, L and Suzuki, H and Sakai, M
Advanced Ceramics and Composites 247 75 - 78 2003
Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Wakamatsu, T. and Tatami, J. and Komeya, K. and Meguro, T.
Key Engineering Materials 247 105 - 108 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of reaction-bonded aluminum nitride from Al powder compacts coated with CaCO3, SrCO3 and BaCO3
Wakamatsu, T and Tatami, J and Komeya, K and Meguro, T and Suzuki, H and Sakai, M
Advanced Ceramics and Composites 247 105 - 108 2003
Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of porous Ca-α SiAlON ceramics
Tatami, J. and Ohta, T. and Zhang, C. and Hotta, M. and Komeya, K. and Meguro, T. and Omori, M. and … Show more authors
Tatami, J. and Ohta, T. and Zhang, C. and Hotta, M. and Komeya, K. and Meguro, T. and Omori, M. and Hirai, T. Hide authors
Ceramic Transactions 142 77 - 87 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Fabrication and evaluation of Ca-α SiAlON nano ceramics
Tatami, J. and Iguchi, M. and Hotta, M. and Zhang, C. and Komeya, K. and Meguro, T. and Omori, M. a … Show more authors
Tatami, J. and Iguchi, M. and Hotta, M. and Zhang, C. and Komeya, K. and Meguro, T. and Omori, M. and Hirai, T. and Brito, M.E. and Cheng, Y.-B. Hide authors
Key Engineering Materials 237 105 - 110 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of Ca-alpha SiAlON nano ceramics
Tatami, J and Iguchi, M and Hotta, M and Zhang, C and Komeya, K and Meguro, T and Omori, M an … Show more authors
Tatami, J and Iguchi, M and Hotta, M and Zhang, C and Komeya, K and Meguro, T and Omori, M and Hirai, T and Brito, ME and Cheng, YB and Mitomo, M Hide authors
Siaions 237 105 - 110 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Tatami, J. and Toyama, M. and Noguchi, K. and Komeya, K. and Meguro, T. and Komatsu, M.
Key Engineering Materials 247 83 - 86 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Effect of TiO2 and AlN additions on the sintering behavior of the Si3N4-Y2O3-Al2O3 system
Tatami, J and Toyama, M and Noguchi, K and Komeya, K and Meguro, T and Komatsu, M and Suzuki, … Show more authors
Tatami, J and Toyama, M and Noguchi, K and Komeya, K and Meguro, T and Komatsu, M and Suzuki, H and Sakai, M Hide authors
Advanced Ceramics and Composites 247 83 - 86 2003 [Reviewed]
Authorship：Lead author, Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Effect of coarser grains on sintering of AlN
Hoshina, T. and Tatami, J. and Meguro, T. and Komeya, K. and Tsuge, A. and Kuibira, A. and Nakata, … Show more authors
Hoshina, T. and Tatami, J. and Meguro, T. and Komeya, K. and Tsuge, A. and Kuibira, A. and Nakata, H. Hide authors
Key Engineering Materials 247 87 - 90 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Effect of coarser grains on sintering of AlN
Hoshina, T and Tatami, J and Meguro, T and Komeya, K and Tsuge, A and Kuibira, A and Nakata, … Show more authors
Hoshina, T and Tatami, J and Meguro, T and Komeya, K and Tsuge, A and Kuibira, A and Nakata, H and Suzuki, H and Sakai, M Hide authors
Advanced Ceramics and Composites 247 87 - 90 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Densification of Ca-αSiAlON nano particles by spark plasma sintering
Iguchi, M. and Tatami, J. and Hotta, M. and Zhang, C. and Komeya, K. and Meguro, T. and Omori, M. a … Show more authors
Iguchi, M. and Tatami, J. and Hotta, M. and Zhang, C. and Komeya, K. and Meguro, T. and Omori, M. and Hirai, T. and Brito, M.E. and Cheng, Y.-B. Hide authors
Key Engineering Materials 247 71 - 74 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Densification of Ca-alpha SiAlON nano particles by spark plasma
Iguchi, M and Tatami, J and Hotta, M and Zhang, C and Komeya, K and Meguro, T and Omori, M an … Show more authors
Iguchi, M and Tatami, J and Hotta, M and Zhang, C and Komeya, K and Meguro, T and Omori, M and Hirai, T and Brito, ME and Cheng, YB and Suzuki, H and Sakai, M Hide authors
Advanced Ceramics and Composites 247 71 - 74 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Corrosion of highly thermal conductive AlN ceramics in aqueous solutions
Lin, CH and Tatami, J and Meguro, T and Komeya, K and Abe, Y and Komatsu, M and Okamoto, M an … Show more authors
Lin, CH and Tatami, J and Meguro, T and Komeya, K and Abe, Y and Komatsu, M and Okamoto, M and Suzuki, H and Sakai, M Hide authors
Advanced Ceramics and Composites 247 235 - 238 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Corrosion of highly thermal conductive AIN ceramics in aqueous solutions
Lin, C.-H. and Tatami, J. and Meguro, T. and Komeya, K. and Abe, Y. and Komatsu, M. and Okamoto, M.
Key Engineering Materials 247 235 - 238 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of beta-SiAlON powder by carbothermal reduction-nitridation of zeolite
Li, FJ and Tatami, J and Meguro, T and Komeya, K and Suzuki, H and Sakai, M
Advanced Ceramics and Composites 247 109 - 112 2003 [Reviewed]
Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of β-SiAlON powder by carbothermal reduction-nitridation of zeolite
Li, F. and Tatami, J. and Meguro, T. and Komeya, K.
Key Engineering Materials 247 109 - 112 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of Ca-α SiAlON hollow balls
Komeya, K. and Tatami, J. and Hotta, M. and Zhang, C. and Meguro, T. and Cheng, Y.-B.
Key Engineering Materials 237 87 - 94 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of Ca-alpha SiAlON hollow balls
Komeya, K and Tatami, J and Hotta, M and Zhang, C and Meguro, T and Cheng, YB and Mitomo, M
Siaions 237 87 - 93 2003
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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ゼオライト結晶化における液相シリカ種と生成物組成の関係
齋藤 誠二郎, 脇原 徹, 小倉 賢, 大久保 達也
化学工学会 研究発表講演要旨集 2003f ( 0 ) 1011 - 1011 2003
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 化学工学会 Joint Work
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ゼオライトの結晶成長時における連続的ツイン形成に伴う周期パターンの発現
脇原 徹, 山北 茂洋, 家住 久美子, 江頭 靖幸, 大久保 達也
化学工学会 研究発表講演要旨集 2003f ( 0 ) 508 - 508 2003
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (research society, symposium materials, etc.) Publisher：公益社団法人 化学工学会 Joint Work
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Effect of α-Si_3N_4 Addition on Sintering of Ma-α-SiAlON Powders
QIU Jin-Yu, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi, CHENG Yi-Bing
Journal of the Ceramic Society of Japan 110 ( 12 ) 1100 - 1102 2002.12 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
Using Mg-α-SiAlON powders synthesized by carbothermal reduction-nitridation, fabrication of Mg-α-SiAlON ceramics was attempted through gas pressure sintering method. Furthermore, the effect of Si<sub>3</sub>N<sub>4</sub> addition on densification of the synthesized powders was investigated. As a result, as-synthesized powders were transformed into β-SiAlON and did not densify during firing. On the other hand, in the case of samples with α-Si<sub>3</sub>N<sub>4</sub> powder, it was found that full densification occurred and the Mg-α-SiAlON phase did not change upon gas pressure sintering, namely, dense Mg-α-SiAlON ceramics, composed of fine and uniform grains, could be obtained through firing at 1950°C for 2h.
Other Link： https://ci.nii.ac.jp/naid/110002288026
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Morphology-retaining synthesis of AlN particles by gas reduction-nitridation
Suehiro T, Tatami J, Meguro T, Matsuo S, Komeya K
MATERIALS LETTERS 57 ( 4 ) 910 - 913 2002.12 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Qiu JY, Tatami J, Zhang C, Komeya K, Meguro T, Cheng YB
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 22 ( 16 ) 2989 - 2996 2002.12 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Fracture behavior of AlN ceramics with rare earth oxides
Terao R, Tatami J, Meguro T, Komeya K
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 22 ( 7 ) 1051 - 1059 2002.7 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of spherical AlN particles by gas-reduction-nitridation method
Suehiro T, Tatami J, Meguro T, Matsuo S, Komeya K
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 22 ( 4 ) 521 - 526 2002.4 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Aluminum nitride fibers synthesized from alumina fibers using gas-reduction-nitridation method
Suehiro T, Tatami J, Meguro T, Komeya K, Matsuo S
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 85 ( 3 ) 715 - 717 2002.3 [Reviewed]
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Aluminum Nitride Fibers Synthesized from Alumina Fibers Using Gas‐Reduction–Nitridation Method
Takayuki Suehiro, Junichi Tatami, Takeshi Meguro, Katsutoshi Komeya, Shuitsu Matsuo
Journal of the American Ceramic Society 85 ( 3 ) 715 - 717 2002.3
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>Aluminum nitride fibers were successfully synthesized from alumina fibers using an NH<jats:sub>3</jats:sub>–C<jats:sub>3</jats:sub>H<jats:sub>8</jats:sub>gas mixture as a reduction–nitridation agent. Observation using SEM clearly demonstrated that the morphology of the nitrided fibers was exactly the same as that of the raw alumina fibers, retaining the original regular shape and smooth surface. Up to 95% of the starting alumina was converted to aluminum nitride at 1400°C within 0.5 h via a single‐step synthesis process.</jats:p>
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多々見 純一
セラミックス 37 ( 2 ) 105 2002.2
Language：English Publishing type：Research paper (scientific journal) Single Work
Other Link： https://ci.nii.ac.jp/naid/10008568879
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Effect of Characteristics of Raw Material on Synthesis of AlN Fibers by Gas-Reduction-Nitridation
J. Ceram. Soc. Jpn. 110 ( 1 ) 67 - 70 2002.1 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Effect of Characteristics of Raw Material on Synthesis of AIN Fibers by Gas-Reduction-Nitridation
SUEHIRO Takayuki, TATAMI Junichi, IDE Takayuki, MEGURO Takeshi, KOMEYA Katsutoshi, MATSUO Shuitsu
Journal of the Ceramic Society of Japan 110 ( 1 ) 67 - 69 2002.1 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
AlN fibers were synthesized by the gas-reduction-nitridation of Al<sub>2</sub>O<sub>3</sub> fibers with different characteristics. The constituent phase in Al<sub>2</sub>O<sub>3</sub> raw fibers changed from γ-Al<sub>2</sub>O<sub>3</sub> to α-Al<sub>2</sub>O<sub>3</sub>, while the surface roughness increased and the specific surface area decreased through the heat treatment. The extent of nitridation of resultant fibers decreased with the decrease in specific surface areas, and with the increase in crystallite size of the raw materials. In particular, the samples transformed to α-Al<sub>2</sub>O<sub>3</sub> were found to have lower reactivity. The enhancement of reduction-nitridation reaction can be attributed to (1) the nitridation progress at a low temperature because of the similarity in crystal structure between AlN and transition aluminas, and (2) the persistence of γ-Al<sub>2</sub>O<sub>3</sub> at a high temperature, due to the suppression of the polymorphic transformation of alumina by the preceding formation of AlN.
Other Link： https://ci.nii.ac.jp/naid/110002291553
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Synthesis of Aluminium Nitride Powder From Aluminum Dross
Austceram 2002 Proceedings 287 - 288 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Effectof Addition of Graphite Powder to Granular Activated Carbon on Thermal Conductivity
Austceram 2002 Proceedings 289 - 290 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabricaton and Evaluation of Porous AlN Polytypoid Ceramics
Abstracts of NCF6 & IMA6 A23 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication of β-SiAlON Nano Ceramics and Evaluation of its Corrosion Resistance
Abstracts of NCF6 & IMA6 41 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Estimation of Short Crack R-curves of Polycrystalline Ceramics by Surface Crack in Flexure Method
Ceramic Transaction 133 115 - 120 2002
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Fracture behavior of AlN ceramics with rare earth oxides
J. Eur. Ceram. Soc. 22 1051 - 1059 2002 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Centrifugal Separation Effect of Furfuryl Alcohol Solution in the Process of Polymerization on Pore Control in Final Resin as a Precursor of Glass Like Carbon
Austceram 2002 Proceedings 261 - 262 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication of Functionally Gradient Material of SiO2-Mo System by Centrifugal Gradation and Floc-casting of Highly Concentrated and Dispersed Slurry
Proceedings of the Second International Conference on Shaping of Advanced Ceramics 83 - 88 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Silicon Nitride Ceramics for Wear Applications
Proceedings of 2nd Fulrath Memorial International Symposium on Advanced Ceramics 67 - 71 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Conversion of Pores in Activated Carbon into Pores with Higher Adsorption Potential by Carbon Deposition According to the Principle of Boudouard Reaction (II)
Austceram 2002 Proceedings 57 - 58 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Corrosion of High Thermal Conductive AlN Ceramics in Aqueous Solutions
Austceram 2002 Proceedings 75 - 76 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Formation Mechanism of Ca-α SiAlON Hollow Balls By TEM Analysis
Austceram 2002 Proceedings 95 - 96 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Evaluation of Characteristics of Activated Carbons with High Surface Area as Electric Double Layer Capacitor
Austceram 2002 Proceedings 121 - 122 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fracture Behavior of AlN Ceramics with Various Rare Earth Oxide Addition
Austceram 2002 Proceedings 211 - 212 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Morphlogy Control of Aluminum Nitrides through Various Reaction Routes
Austceram 2002 Proceedings 255 - 256 2002
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Evaluation of corrosion resistance of β-sialon nano ceramics
Nagatome Azuma, Li Qiang, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Omori Mamoru, Hirai To … Show more authors
Nagatome Azuma, Li Qiang, Tatami Junichi, Komeya Katsutoshi, Meguro Takeshi, Omori Mamoru, Hirai Toshio Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2002 ( 0 ) 57 - 57 2002
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
In our previous work, we synthesized β-sialon nano powders by carbothermal reduction-nitridation of SiO<SUB>2</SUB>-Al<SUB>2</SUB>O<SUB>3</SUB> mixture, and fabricated β-sialon nano ceramics using it by spark plasma sintering method. The purpose of this study is to evaluate its corrosion resistance in various aqueous solutions. The relative density of the sintered body was over 99% under firing condition of 1800.C, 5min. As a result of corrosion test, it was found to be better corrosion resistance in H<SUB>2</SUB>SO<SUB>4</SUB> than commercial Si<SUB>3</SUB>N<SUB>4</SUB> ceramics.
Other Link： https://ci.nii.ac.jp/naid/130006967865
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Fabrication of Porous AlN from Porous AlN polytypoid
Furukawa Yuko, Tatami Juniti, Komeya Katsutoshi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2002 ( 0 ) 304 - 304 2002
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Porous AlN was fabricated by carbothermal reduction-nitridation of AlN polytypoid of Si-Al-O-N system. The Thermal conductivity depended on not only the porosity but also the microstructure. In particular, porous AlN ceramics fabricated from the AlN polytypoid with 10wt% SiO<SUB>2</SUB> addition had high thermal conductivity (50W/mK), high porosity (54%) and low dielectric constant (3.0 at 1MHz). Consequently, this porous AlN ceramics is expected to be used under a high frequency.
Other Link： https://ci.nii.ac.jp/naid/130006970092
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Synthesis of AlN nanoparticles by gas reduction-nitridation
Suehiro Takayuki, Komeya Katsutoshi, Tatami Junichi, Meguro Takeshi
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2002 ( 0 ) 92 - 92 2002
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Aluminum nitride nanoparticles were successfully synthesized from transition alumina nanoparticles using an NH<SUB>3</SUB>-C<SUB>3</SUB>H<SUB>8</SUB> gas mixture as a reduction-nitridation agent. Phase-pure, nanocrystalline AlN powder with primary particle size of 30 nm and specific surface area of 36 m<SUP>2</SUP>/g was prepared under typical reaction condition. Produced AlN nanoparticles possess excellent sinterability, allowing full densification under conventional processing conditions even without the addition of sintering aids.
Other Link： https://ci.nii.ac.jp/naid/130006967684
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Analysis of inhomogeneity of sintering in aluminum nitride based on local porosity
Tatami Junichi, Namiki Masahiro, Meguro Takeshi, Komeya Katutoshi, Naito Makio, Hotta Tadashi, Kuib … Show more authors
Tatami Junichi, Namiki Masahiro, Meguro Takeshi, Komeya Katutoshi, Naito Makio, Hotta Tadashi, Kuibira Akira, Nakata Hirohiko Hide authors
Preprints of Annual Meeting of The Ceramic Society of Japan<br>Preprints of Fall Meeting of The Ceramic Society of Japan 2002 ( 0 ) 374 - 374 2002
Language：English Publishing type：Research paper (research society, symposium materials, etc.) Publisher：The Ceramic Society of Japan Joint Work
Influence of coarser grains on sintering of AlN was investigated. Densification of AlN was limited by addition of coarser grains. Large pores were observed near the coarser grains. Local porosity showed higher value in the vicinity of coarser grain than any other area. It was found that the pore grew up during sintering. These phenomena probably resulted from not only inhomogeneity of density of green body but also insufficiency of oxygen near coarser grain.
Other Link： https://ci.nii.ac.jp/naid/130006968387
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Yasuda K, Taguchi T, Tatami J, Matsuo Y
IMPROVED CERAMICS THROUGH NEW MEASUREMENTS, PROCESSING, AND STANDARDS 133 115 - 120 2002
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Mechanical properties of AlN ceramics with various rare earth oxides
Proceedings of The 18th International Korea-Japan Seminar on Ceramics 444 - 448 2001.12
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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IDE Takayuki, KOMEYA Katsutoshi, SUEHIRO Takayuki, TATAMI Junichi, MEGURO Takeshi, NAITO Makio, HOT … Show more authors
IDE Takayuki, KOMEYA Katsutoshi, SUEHIRO Takayuki, TATAMI Junichi, MEGURO Takeshi, NAITO Makio, HOTTA Tadashi, KUIBIRA Akira Hide authors
Journal of the Ceramic Society of Japan 109 ( 12 ) 1051 - 1054 2001.12 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
The effect of addition of binary system CaO-Y<sub>2</sub>O<sub>3</sub> on the synthesis of AlN powder by carbothermal reductionnitridation of Al<sub>2</sub>O<sub>3</sub> was investigated. The nitridation was conducted at 1450°C in N<sub>2</sub> gas flow. The morphology of synthesized powders was different from the original Al<sub>2</sub>O<sub>3</sub> powder. The XRD analysis showed that the reaction progressed through formation of several aluminates during nitridation. These aluminates were confirmed to promote the nitridation and vary the morphology of raw Al<sub>2</sub>O<sub>3</sub>. The amount of additives remained in final product is smaller than that of starting powder. This synthesized powder is considered to be advantageous to the densification because remaining compounds can act as a sintering aid.
Other Link： https://ci.nii.ac.jp/naid/110002288967
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40 ( 8 ) 5041 - 5045 2001.8 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Microstructural Observation of Silicon Nitride Ceramics Sintered with Addition of Titania.
YANO Toyohiko, TATAMI Junichi, KOMEYA Katsutoshi, MEGURO Takeshi
Journal of the Ceramic Society of Japan 109 ( 5 ) 396 - 400 2001.5 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
Other Link： https://ci.nii.ac.jp/naid/110002288793
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Effect of HfO_2 Addition on Sintering of Si_3N_4
LI Huang, KOMEYA Katsutoshi, TATAMI Junichi, MEGURO Takeshi, CHIBA Yoshihiko, KOMATSU Michiyasu
Journal of the Ceramic Society of Japan 109 ( 4 ) 342 - 346 2001.4 [Reviewed]
DOI Web of Science Scopus CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
The effect of HfO<sub>2</sub> addition on sintering of Si<sub>3</sub>N<sub>4</sub>-Y<sub>2</sub>O<sub>3</sub>-AlN system was investigated. Although the densification was improved by the addition of HfO<sub>2</sub>, the behavior was divided into two types according to the selected firing temperature: below 1800°C, the maximum density was achieved with 1.5mass% HfO<sub>2</sub> addition; on the other hand, above 1800°C density continuously increased with increasing HfO<sub>2</sub> addition. This densification behavior could be explained according to phase diagrams of the HfO<sub>2</sub>-Y<sub>2</sub>O<sub>3</sub>⋅SiO<sub>2</sub> (eutectic temperature: 1800°C) and HfO<sub>2</sub>-Y<sub>2</sub>O<sub>3</sub>⋅2SiO<sub>2</sub> (eutectic temperature: 1600°C). As a tentative mechanism for densification, it was considered that, in the initial stage of sintering, the formation of some liquid phases with low melting point promoted densification. Then precipitation of <i>c</i>-HfO<sub>2</sub> including Y, Si elements and of HfN including O occurred. This mechanism was supported by X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy dispersive spectrometry (EDS) analysis. The phase transformation from α-Si<sub>3</sub>N<sub>4</sub> to β-SiAlON was found to be enhanced by HfO<sub>2</sub> addition. Consequently, sintered bodies obtained from the Si<sub>3</sub>N<sub>4</sub>-Y<sub>2</sub>O<sub>3</sub>-AlN-HfO<sub>2</sub> mixtures were consisted of not only elongated β-SiAlON grains, and grain-boundary phases composed of Hf, Si, Al, Y and O, but also isolated spherical grains of both <i>c</i>-HfO<sub>2</sub> and HfN (200-400nm in diameter).
Other Link： https://ci.nii.ac.jp/naid/110002288778
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多々見 純一
粉体工学会誌 38 ( 1 ) 46 2001.1 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Single Work
Other Link： https://ci.nii.ac.jp/naid/10010064911
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CONVERSION OF PORES IN ACTIVATED CARBON INTO PORES WITH HIGHER ADSORPTION POTENTIAL BY CARBON DEPOSITION ACCORDING TO THE PRINCIPLE OF BOUDOUARD REACTION
Katsutoshi Komeya, Hirobumi Tanaka, Takeshi Meguro, Junichi Tatami
Processing and Fabrication of Advanced Materials VIII 611 - 617 2001.1 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：World Scientific Pub Co Pte Ltd Joint Work
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CORROSION RESISTANCE OF SILICON NITRIDE CERAMICS IN AQUEOUS SOLUTION
Katsutoshi Komeya, Motohiro Kobayashi, Takeshi Meguro, Shinji Atago, Michiyasu Komatsu, Junichi Tat … Show more authors
Katsutoshi Komeya, Motohiro Kobayashi, Takeshi Meguro, Shinji Atago, Michiyasu Komatsu, Junichi Tatami, Yutaka Abe, Chin Ho Lin Hide authors
Processing and Fabrication of Advanced Materials VIII 603 - 610 2001.1 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：World Scientific Pub Co Pte Ltd Joint Work
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Preparation of Mg-α Sialon Powder by Carbothermal Reduction-Nitridation of Talc and Halloysite
J. Aust. Ceram. Soc. 37 ( 1 ) 45 - 50 2001 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of Nano-Size Ca-α Sialon Powders by Carbothermal Reduction-Nitridation
J. Aust. Ceram. Soc. 36 ( 2 ) 115 - 120 2001 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Si3N4-Y2O3-Al2O3系にTiO2, AlNを添加した焼結体の空気酸化挙動
小林基宏, 目黒竹司, 米屋勝利, 野口和則, 横山隆, 多々見純一,
材料科学 38 ( 1 ) 49 - 58 2001 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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TiO2/AlN添加系Si3N4-Y2O3-Al2O3焼結体の空気酸化により生じる酸化層のEPMAによる解析
目黒竹司, 米屋勝利, 小林基宏, 横山隆, 野口和則,多々見純一,
材料科学 38 ( 4 ) 150 - 57 2001 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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Synthesis and properties of LiMnO2 for lithium battery
Takahsshi F, Komeya K, Tatami J, Meguro T, Sasamoto T, Nishikawa R
PROCEEDINGS OF THE FIRST CHINA INTERNATIONAL CONFERENCE ON HIGH-PERFORMANCE CERAMICS 403 - 405 2001
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Transient liquid phase sintering of silicon nitride with yttria, aluminum nitride and hafnia
Li H, Komeya K, Meguro T, Tatami J, Chiba Y, Kameda T
PROCEEDINGS OF THE FIRST CHINA INTERNATIONAL CONFERENCE ON HIGH-PERFORMANCE CERAMICS 296 - 298 2001
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of Mg-alpha SiAlON powders from talc and halloysite clay minerals
Zhang C, Komeya K, Tatami J, Meguro T, Cheng YB
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 20 ( 11 ) 1809 - 1814 2000.10 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Injuries of the thoracolumbar spine associated with restraint use in head-on motor vehicle accidents
Ball, ST; Vaccaro, AR; Albert, TJ; Cotler, JM
JOURNAL OF SPINAL DISORDERS 13 ( 4 ) 297 - 304 2000.8 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Zhang C, Komeya K, Tatami J, Meguro T
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 20 ( 7 ) 939 - 944 2000.6 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Control of grain morphology in Ca-alpha sialon ceramics by changing the heating rate
Zhang C, Narimatsu E, Komeya K, Tatami J, Meguro T
MATERIALS LETTERS 43 ( 5-6 ) 315 - 319 2000.5 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Hollow beads composed of nanosize Ca alpha-SiAlON grains
Komeya K, Zhang C, Hotta M, Tatami J, Meguro T, Cheng YB
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 83 ( 4 ) 995 - 997 2000.4 [Reviewed]
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>Carbothermal reduction—nitridation (CRN) of SiO<jats:sub>2</jats:sub> is an attractive method to manufacture Si<jats:sub>3</jats:sub>N<jats:sub>4</jats:sub> powders with controlled grain morphology. Moreover, β‐SiAlON powders could also be synthesized from either pure powder mixture or some inexpensive raw minerals by CRN and the resulting powders favored the sintering of SiAlON product. However, there have been few works on preparing α‐SiAlON powders so far. In this work, Ca α‐SiAlON powder was synthesized by CRN of a SiO<jats:sub>2</jats:sub>—Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>—CaCO<jats:sub>3</jats:sub> mixture. An unusual morphology of hollow beads 200 to 500 nm in diameter with a great deal of nanosize α‐SiAlON particles around 10 to 30 nm in diameter was observed from the resultant Ca α‐SiAlON powders, which has not been reported for SiAlON ceramics before.</jats:p>
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Fracture Behavior Of Strengthened AlN
Ceramic Transactions 106 493 - 499 2000
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Search of New Additives to Improve Mechanical Strength of AlN Ceramics
Ceramic Transactions 106 501 - 507 2000
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of Ca-α Sialon Hollow Ball by Carbothermal Reduction-Nitridation
Ceramic Transactions 112 707 - 712 2000
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Key Components for Morphology Control of Nitride Ceramics
Proceedongs of the 10 th Iketani Conference Materials Research toward the 21 th Century 161 - 162 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of porous AlN polytypoid
Proceedings of The 17th International Korea-Japan Seminar on Ceramics 289 - 93 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of spherical AlN powder by reduction-nitridation using NH3-C3H8 gas
Proceedings of The 17th International Korea-Japan Seminar on Ceramics 317 - 321 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fracture behavior of AlN-Y2O3-alkaline earth oxide system
Proceedings of The 17th International Korea-Japan Seminar on Ceramics 488 - 492 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and evaluation of PVD-TiN/Si3N4
Proceedings of The 17th International Korea-Japan Seminar on Ceramics 498 - 501 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Liquid phase sintering behavior of AlN-Y2O3-CaO
Proceedings of the 17th International Korea-Japan Seminar on Ceramics 52 - 55 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fabrication and Evaluation of PVD TiN Coated Si3N4
Proceedongs of the 10 th Iketani Conference Materials Research toward the 21 th Century 211 - 212 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Synthesis of Ca-α Sialon Hollow Ball by Carbothermal Reduction-Nitridation Method
Proceedongs of the 10 th Iketani Conference Materials Research toward the 21 th Century 243 - 244 2000
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Fracture behavior of strengthened AIN
Tatami J, Komeya K, Meguro T, Iwasawa S, Terao R, Komatsu M
ELECTRONIC CERAMIC MATERIALS AND DEVICES 106 493 - 499 2000
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Search for new additives to improve mechanical strength of an ceramics
Komeya K, Terao R, Tatami J, Meguro T
ELECTRONIC CERAMIC MATERIALS AND DEVICES 106 501 - 507 2000 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Identification of Dislocations on Fracture Surface of Single Crystal Alumina by X-Ray Topography.
TATAMI Junichi, SAIKI Atsushi, YASUDA Kouichi, MATSUO Yohtaro
Journal of the Ceramic Society of Japan 107 ( 11 ) 1063 - 1066 1999.11 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Synthesis of AlN powder by carbothermal reduction-nitridation of various Al2O3 powders with CaF2
Ide T, Komeya K, Meguro T, Tatami J
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 82 ( 11 ) 2993 - 2998 1999.11 [Reviewed]
Language：English Publishing type：Research paper (scientific journal) Joint Work
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Synthesis of AlN Powder by Carbothermal Reduction‐Nitridation of Various Al2O3 Powders with CaF2
Takayuki Ide, Katsutoshi Komeya, Takeshi Meguro, Junichi Tatami
Journal of the American Ceramic Society 82 ( 11 ) 2993 - 2998 1999.11
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>We investigated the effect of characteristics of raw Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> powder on the synthesis of AlN by the carbothermal reduction‐nitridation method, in which CaF<jats:sub>2</jats:sub> was added as a catalytic material. Four types of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> powders were selected. An Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/C molar ratio of 0.29 was fixed, and the amount of CaF<jats:sub>2</jats:sub> was varied from 3 to 30 wt%. The carbothermal reduction‐nitridation was conducted from 1350° to 1450°C in N<jats:sub>2</jats:sub> flow. The nitridation rate tended to increase with decreasing particle size of raw Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and was found to depend on the Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> synthesizing method. The particle sizes of the synthesized AlN increased somewhat with increasing reaction temperatures. However, even though different particle sizes of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> powders were used, AlN powders synthesized under the same conditions exhibited almost the same particle size, round shape, and narrow size distribution. From XRD analysis, CaO·6Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and CaO·2Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> were identified as intermediate compounds during these reactions. The above phenomena suggest that the synthesis mechanism of AlN powder by carbothermal reduction‐nitridation of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> with CaF<jats:sub>2</jats:sub> addition was the nitridation of the intermediate compounds through the liquid phase of the system CaF<jats:sub>2</jats:sub>‐CaO·6Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐CaO·2Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>.</jats:p>
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Synthesis of AlN Powder by Carbothermal Reduction‐Nitridation of Various Al2O3 Powders with CaF2
Takayuki Ide, Katsutoshi Komeya, Takeshi Meguro, Junichi Tatami
Journal of the American Ceramic Society 82 ( 11 ) 2993 - 2998 1999.11
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work
<jats:p>We investigated the effect of characteristics of raw Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> powder on the synthesis of AlN by the carbothermal reduction‐nitridation method, in which CaF<jats:sub>2</jats:sub> was added as a catalytic material. Four types of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> powders were selected. An Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>/C molar ratio of 0.29 was fixed, and the amount of CaF<jats:sub>2</jats:sub> was varied from 3 to 30 wt%. The carbothermal reduction‐nitridation was conducted from 1350° to 1450°C in N<jats:sub>2</jats:sub> flow. The nitridation rate tended to increase with decreasing particle size of raw Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and was found to depend on the Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> synthesizing method. The particle sizes of the synthesized AlN increased somewhat with increasing reaction temperatures. However, even though different particle sizes of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> powders were used, AlN powders synthesized under the same conditions exhibited almost the same particle size, round shape, and narrow size distribution. From XRD analysis, CaO·6Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and CaO·2Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> were identified as intermediate compounds during these reactions. The above phenomena suggest that the synthesis mechanism of AlN powder by carbothermal reduction‐nitridation of Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> with CaF<jats:sub>2</jats:sub> addition was the nitridation of the intermediate compounds through the liquid phase of the system CaF<jats:sub>2</jats:sub>‐CaO·6Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐CaO·2Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>.</jats:p>
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Effect of Raw Powder Characteristics on the Compactibilty and Sinterability in Non-oxide Ceramics
KOMEYA Katsutoshi, MEGURO Takeshi, TATAMI Junichi, NAITO Makio
Ceramics Japan 34 ( 10 ) 816 - 820 1999.10
Language：English Publishing type：Research paper (scientific journal) Joint Work
Other Link： https://ci.nii.ac.jp/naid/10005144169
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Twist Angle Dependence of Interfacial Fracture Toughness of (0001)Twist Boundary of Alumina
Key Engineering Materials 161-163 573 - 576 1999
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Derivation of Crack Path in Particle-Dispersed Ceramic Composites by Finite Element Method
Key Engineering Materials 161-163 577 - 580 1999
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Corrosion Resistance of Silicon Nitride Ceramics in Aqueous Solution
Processing and Fabrication of Advanced Materials ⅷ 603 - 610 1999
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Conversion of Pores in Activated Carbon Into Pores with Higher Adsorption Potential by Carbon Deposition According to the Principal of Boudouard Reaction
Processing and Fabrication of Advanced Materials ⅷ 611 - 617 1999
Language：English Publishing type：Research paper (international conference proceedings) Joint Work
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Derivation of crack path in particle-dispersed ceramic composites by finite element method
Yasuda K, Sekiguchi Y, Tatami J, Matsuo Y
SCIENCE OF ENGINEERING CERAMICS II 2 577 - 580 1999
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
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Twist angle dependence of interfacial fracture toughness of (0001) twist boundary of alumina
Yasuda K, Tatami J, Harada T, Matsuo Y
SCIENCE OF ENGINEERING CERAMICS II 2 573 - 576 1999
DOI Web of Science CiNii Research
Language：English Publishing type：Research paper (scientific journal) Publisher：Trans Tech Publications, Ltd. Joint Work
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Derivation of Crack Path in Particle-Dispersed Ceramic Composites by Finite Element Method
Yasuda, K. and Sekiguchi, Y. and Tatami, J. and Matsuo, Y.
Key Engineering Materials 161-163 577 - 580 1999
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Fracture behavior of high thermal conductive aluminum nitride
Tatami, J. and Komeya, K. and Meguro, T. and Iwasawa, S. and Komatsu, M.
Ceramic Engineering and Science Proceedings 20 ( 3 ) 411 - 418 1999
Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Derivation of crack path in particle-dispersed ceramic composites by finite element method
Yasuda, K and Sekiguchi, Y and Tatami, J and Matsuo, Y and Niihara, K and Sekino, T and Yasud … Show more authors
Yasuda, K and Sekiguchi, Y and Tatami, J and Matsuo, Y and Niihara, K and Sekino, T and Yasuda, E and Sasa, T Hide authors
Science of Engineering Ceramics Ii 2 577 - 580 1999
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Twist Angle Dependence of Interfacial Fracture Toughness of (0001) Twist Boundary of Alumina
Yasuda, K. and Tatami, J. and Harada, T. and Matsuo, Y.
Key Engineering Materials 161-163 573 - 576 1999
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (international conference proceedings) Joint Work
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Twist angle dependence of interfacial fracture toughness of (0001) twist boundary of alumina
Yasuda, K and Tatami, J and Harada, T and Matsuo, Y and Niihara, K and Sekino, T and Yasuda, … Show more authors
Yasuda, K and Tatami, J and Harada, T and Matsuo, Y and Niihara, K and Sekino, T and Yasuda, E and Sasa, T Hide authors
Science of Engineering Ceramics Ii 2 573 - 576 1999
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Evaluation of fracture toughness of (0001) twist boundary using alumina bicrystal
J. Ceram. Soc. Japan 106 ( 4 ) 372 - 376 1998.4 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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Influence of twist angle on the fracture toughness of (0001) twist boundary of alumina
Tatami J, Harada T, Yasuda K, Matsuo Y
22ND ANNUAL CONFERENCE ON COMPOSITES, ADVANCED CERAMICS, MATERIALS, AND STRUCTURES: A 19 ( 3 ) 211 - 218 1998
Authorship：Corresponding author Language：English Publishing type：Research paper (research society, symposium materials, etc.) Joint Work
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Tatami J, Yasuda K, Matsuo Y, Kimura S
MATERIALS SCIENCE AND ENGINEERING SERVING SOCIETY 69 - 72 1998
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Influence of twist angle on the fracture toughness of (0001) twist boundary of alumina
Tatami, Junichi and Harada, Tamotsu and Yasuda, Kouichi and Matsuo, Yohtaro
Ceramic Engineering and Science Proceedings 19 ( 3 ) 211 - 218 1998
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Joint Work
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Wavelet and Fourier Transformations for Crack Path of Particle-dispersed Ceramic Composites
YASUDA Kouichi, IKEDA Koichiro, TATAMI Junichi, MATSUO Yohtaro
49 ( 11 ) 615 1997.11
Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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Tatami J, Yasuda K, Matsuo Y, Kimura S
JOURNAL OF MATERIALS SCIENCE 32 ( 9 ) 2341 - 2346 1997.5 [Reviewed]
DOI Web of Science CiNii Research
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Netherlands Joint Work
The crack path of polycrystalline ceramics has been theoretically analysed with a stochastic model based on the difference between the released energies in intergranular and transgranular crack propagation. Assuming that the path with the lowest released energy should be realized as the actual crack path, the expected values of the fraction of transgranular fracture on fracture surface and the fracture toughness of polycrystalline ceramics were formulated as functions of grain size and the critical energy release rates of grain and grain boundary. By comparison between the theory and the experimental results it was shown that the stochastic model proposed here expressed the change of the crack path and the fracture toughness of polycrystalline Al2O3, relative to grain size.
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安田 公一, 多々見 純一, 松尾 陽太郎
材料科学 : 日本材料科学会誌 33 ( 6 ) 298 - 304 1996.11 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本材料科学会 Joint Work
資料形態 : テキストデータ プレーンテキスト
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Influence of crack path on the fracture toughness of polycrystalline Al2O3
Yasuda K, Tatami J, Matsuo Y, Kimura S
FRACTURE MECHANICS OF CERAMICS, VOL 11 11 315 - 330 1996
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Influence of Fracture Surface Interactions on Fracture Toughness Measured by Chevron Notched Beam Method
J. Ceram. Soc. Japan 103 ( 4 ) 357 - 364 1995.4 [Reviewed]
Authorship：Lead author Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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TATAMI Junichi, KIMURA Shiushichi, MATSUO Yohtaro, YASUDA Kouichi
Journal of the Ceramic Society of Japan 103 ( 4 ) 357 - 364 1995.4
DOI Web of Science CiNii Research
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Influence of crack propagation path on the fracture toughness of ceramic composite
Tatami J, Yasuda K, Matsuo Y, Kimura S
COMPOSITES '95: RECENT ADVANCES IN JAPAN AND THE UNITED STATES 135 - 142 1995
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work
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Stochastic analysis for influence of grain size on fraction of transgranular fracture in polycrystalline ceramics
Journal of the Ceramic Society of Japan 102 ( 9 ) 887 - 889 1994.9 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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YASUDA Kouichi, TATAMI Junichi, MATSUO Yohtaro, KIMURA Shiushichi
Journal of the Ceramic Society of Japan 102 ( 1189 ) 887 - 889 1994 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work
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Influence of crack propagation path on the fracture toughness of polycrystalline Al2O3
J. Ceram. Soc. Japan 101 ( 12 ) 1384 - 1389 1993.12 [Reviewed]
Language：Japanese Publishing type：Research paper (scientific journal) Joint Work
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YASUDA Kouichi, TATAMI Junichi, ASADA Kazutoshi, MATSUO Yohtaro, KIMURA Shiushichi
Journal of the Ceramic Society of Japan 101 ( 1180 ) 1384 - 1389 1993 [Reviewed]
Authorship：Corresponding author Language：The in addition, foreign language Publishing type：Research paper (scientific journal) Publisher：The Ceramic Society of Japan Joint Work