METHOD FOR PRODUCING SIC FIBER/SIC COMPOSITE MATERIAL HAVING HIGH STRENGTH

摘要

A method for producing a SiC fiber/SiC composite material having high strength, which comprises impregnating a SiC fiber formed product with a polyvinyl silane having unit structures (a) and (b) in a (a)/(b) ratio of 1, heating the resultant resin-impregnated SiC fiber formed product to a temperature of 300 to 400 DEG in an inert gas atmosphere to thereby convert the polyvinyl silane to a high viscous liquid or a semi-solid, and then firing the resultant product in an Argon gas atmosphere while pressuring uniaxially. The method provides a SiC fiber/SiC composite material which has a high tightness and is excellent in mechanical properties and high temperature characteristics. The use of the polyvinyl silane containing an amount less than 50 mass % of fine SiC particles incorporated homogeneously therein and repeated impregnation with the polyvinyl silane and firing with no pressuring after the above firing under pressure provide a SiC fiber/SiC composite material having a higher density.