Method of producing dense sintered silicon carbide body from polycarbosilane

A method for producing a dense, sintered silicon carbide body from polycarbosilane comprising the steps of:

• (a) polymerizing a organosilicon so as to form a polycarbosilane which is insoluble in organic solvent and has a melting or softening temperature which is higher than its thermal decomposition temperature;
• (b) forming said polycarbosilane into a powder;
• (c) thermally decomposing said powder at 600.degree. to 2200.degree. C. in a nonoxidizing atmosphere to obtain silicon carbide;
• (d) molding said silicon carbide powder;
• and
• (e) sintering the molded body formed in step (d) in a nonoxidizing atmosphere thereby forming a dense, sintered silicon carbide body.

A method of producing a dense sintered silicon carbide body from polycarbosilane, which comprises the steps of:

• (a) polymerizing an organosilicon compound so as to form a polycarbosilane which is insoluble organic solvent and has a melting or softening temperature which is higher than its thermal decomposition temperature;
• (b) forming said polycarbosilane into a powder;
• (c) thermally decomposing said powder at 600.degree. to 2200.degree. in a nonoxidizing atmosphere to obtained silicon carbide powder;
• (d) adding a sintering aid to said silicon carbide powder;
• (e) molding said silicon carbide powder and sintering aid mixture;
• and
• (f) sintering the molded body formed in step (e) in a nonoxidizing atmosphere thereby forming said dense sintered silicon carbide body.