| 摘要 |
PURPOSE:To increase porosity, uniformalize crystal size and pore size, and increase an effective surface area in contact with fluid by molding a mixture of a SiC powder and molding binder and subjecting to primary sintering, de- carbon treating and secondary sintering. CONSTITUTION:A molding binder (e.g. methyl cellulose) is added to a mixture of a SiC powder containing >=70wt.% beta-type SiC and a crystal growth auxiliary (e.g. Al) as necessary and molded to a fixed shape to obtain a raw molded material. Next, the raw molded material is dewaxed by heating by 700-800 deg.C for 1-2 hour in an inert gas atmosphere and sintering at 1500-1900 deg.C for 0.5-2 hour to obtain a first sintered material. Then, said sintered material is subjected to de-carbon treatment by heating at 400-900 deg.C for 1-4 hour, thus to secondary sintering by heating at 2000-2400 deg.C for 2-6 hour to afford aimed SiC sintered porous material having 20-95vol% porosity and 5-50mum pore size. |
