SILICON-SILICON CARBIDE MATERIAL WITH SILICON CONCENTRATION GRADIENT AND SILICON CARBIDE FIBER REINFORCED SILICON-SILICON CARBIDE COMPOSITE MATERIAL WITH SILICON CONCENTRATION GRADIENT AND THEIR PRODUCTION

摘要

PROBLEM TO BE SOLVED: To produce an Si-SiC material with an Si concn. gradient capable of remarkably improving corrosion resistance and strength in a highly oxidation- corrosive environment and healing function to defects in the surface and central layers and to produce an SiC fiber reinforced Si-SiC composite material with an Si concn. gradient. SOLUTION: Silicon is melted and impregnated into a compact contg. SiC particles to obtain the objective Si-SiC material having <=1.0% porosity. The concn. of Si in the Si-SiC material lowers from the surface layer toward the central layer. Silicon is melted and impregnated into a compact contg. SiC fibers and SiC particles to obtain the objective SiC fiber reinforced Si-SiC composite material having <=1.0% porosity. The concn. of Si in the Si-SiC composite material lowers from the surface layer toward the central layer.