| 摘要 |
PURPOSE:To obtain a ceramic sintered member having high strength at high temp. and excellent in oxidation resistance by providing a surface layer composed of alumina particles with an average particle size of a predetermined value or more on a substrate composed of silicon nitride. CONSTITUTION:A ceramic sintered member consists of a substrate 1 composed of silicon nitride and the surface layer composed of alumina particles with an average particle size of 20mum or more formed on the substrate. As mentioned above, the ceramic sintered member has such a structure that the surface layer 2 composed of alumina particles excellent in oxidation resistance and corrosion resistance is formed on the substrate composed of silicon nitride excellent in strength and tenacity. Therefore, the surface of the substrate 1 is protected by the surface layer 2 and prevented from being directly exposed to an oxidative or corrosive atmosphere. Since the surface layer is composed of alumina particles with an average particle size of 20mum or more, even if tensile residual stress is applied to the surface layer by the difference of the coefficient of thermal expansion with the substrate 1 composed of silicon nitride, the surface layer has strength withstanding tensile residual stress. |
