| 摘要 |
PURPOSE:To easily obtain a fine-grained dense silicon carbide sintered body having high density and low surface roughness by adding a sintering aid having a specified compsn. to fine silicon carbide powder and carrying out sintering by hot pressing under controlled temp. and pressure. CONSTITUTION:Silicon carbide powder of <=0.5mum average particle size is prepd. and 70-99wt.% of this powder is blended with 0.7-20wt.% aluminum oxide and 0.3-20wt.% silicon oxide as a sintering aid in 0.4-1 weight ratio of silicon oxide to aluminum oxide. The resulting powdery mixture is sintered by hot pressing at 1,700-1,950 deg.C under >=10MPa pressure in an atmosphere of gaseous Ar to obtain a dense silicon carbide sintered body having <=0.5mum average grain size, >=99% relative density and low surface roughness. Since the aluminum oxide and silicon oxide added as a sintering aid form a liq. phase at a relatively low temp., the sintered body can be made dense at the relatively low sintering temp. |
