| 摘要 |
PURPOSE:To obtain porous ceramic uniform in pore diameter, having uniform gas permeability, capable of precision machining and giving a large-sized article. CONSTITUTION:Calcined alumina powder and a siliceous sintering aid are added to aggregate particles based on spherical alumina particles having 10-100mum average particle diameter by 5-30wt.% and 20-70wt.% of the amt. of the aggregate particles, respectively. The interior of each of the alumina particles is made of alpha-Al2O3 and the surface layer consists of gamma-Al2O3, delta-Al2O3 and theta-Al2O3. The resulting blend is compacted and fired to obtain the objective porous ceramic especially suitable for use as a microporous filter for blowing gas or an oil impregnated bearing material. |
