| 摘要 |
PURPOSE:To obtain alpha-sialon enhanced in high-temperature strength and toughness by adding ultrafine silicon carbide powder to alpha-sialon powder and forming the mixture and burning the formed article. CONSTITUTION:5-35 pts.wt. silicon carbide powder having <=0.1mu grain size is added to 100 pts.wt. alpha-sialon powder and the mixture is formed and burned provide the objective sintered compact. Grain size of alpha-sialon powder used is preferably about <=0.6mu in average. A starting raw material consisting of alpha-sialon powder and SiC powder is formed and then burned under ordinary pressure, preferably in nitrogen atmosphere at 1700-1800 deg.C. According to the above-mentioned production method, dense alpha-sialon sintered compact can be obtained in ordinary-pressure sintering by adding ultrafine-grain SiC to '-sialon powder. Presence of the ultrafine-grain Si in alpha-sialon prevents a movement by slipping of grain boundaries and movement by deformation of grains and lowers creep rate and improves high-temperature strength and toughness. |
