| 摘要 |
PURPOSE:To obtain the title sintered body having high strength, high toughness and superior durability even in a severe erosive environment by sintering a solid soln. consisting of prescribed amts. of Al2O3 and Cr2O3 as starting material and by aging the sintered body at a high temp. in a nonoxidizing atmosphere to precipitate gamma-Al2O3 in the solid soln. CONSTITUTION:Powder of a solid soln. consisting of 80-90wt.% Al2O3 of <=5mum grain size and 20-10wt.% Cr2O3 of <=5mum grain size as starting material is molded and sintered at 1,500-1,850 deg.C to form an Al2O3-based sintered body, e.g., having 20-35kg/mm<2> bending strength and about 3MN/m<-2/3> fracture toughness. Thus sintered body is aged at 1,000-1,180 deg.C in a nonoxidizing atmosphere to precipitate gamma-Al2O3 in the solid soln. The title sintered body having 45-60kg/mm<2> bending strength and 6-8MN/m<-2/3> fracture toughness is obtd. |
