Project/Area Number |
04650692
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
無機工業化学・無機材料工学
|
Research Institution | Nagoya University |
Principal Investigator |
KOUMOTO Kunihito Nagoya University, School of Eng. Professor, 工学部, 教授 (30133094)
|
Co-Investigator(Kenkyū-buntansha) |
WON Son Seo Nagoya University, School of Research Assoc., 工学部, 助手 (30242829)
|
Project Period (FY) |
1992 – 1993
|
Project Status |
Completed (Fiscal Year 1993)
|
Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1993: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1992: ¥1,500,000 (Direct Cost: ¥1,500,000)
|
Keywords | Silicon carbide / Stacking fault / Grain growth / Surface diffusion / High-temperature / Reaction rate / Formation / Annihilation / 炭化ケイ素 / 積層欠陥 / 粒成長 / 表面拡散 / 拡散律速 / 速度論 |
Research Abstract |
Annihilation of stacking faults in beta-SiC was found to occur simultaneously with grain growth during high-temperature sintering. Analyzes of the rate process by use of the Avrami-Erofeev equation indicated that the rate of annihilation of stacking faults was controlled by the atomic diffusion process. The rate of grain growth, on the other hand, was found to be limited by surface diffusivity. Coincidence in the values of activation energy for the two processes suggested that the annihilation of stacking faults is an apparent phenomenon resulting from the microstructural evolution in which the grain growth is controlled by surface diffusivity. Incorporation of nitrogen during heating suppressed the surface diffusivity and hence, the rate of stacking fault annihilation. Formation of stacking faults during the synthesis of beta-SiC by cabothermal reduction of silica was also investigated and we found that two kinds of morphology, whisker and sphere, were always observed for the synthesized powder, and that a larger amount of stacking faults were containde in whiskers than in spherical particles.
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