| 摘要 |
PROBLEM TO BE SOLVED: To attempt a pore-free state and improve wearing resistance, fracture toughness and shock resistance by firing a powdery mixture of Al2 O3 with a metal boride, an antioxidant and a sintering aid and carrying out hot isostatic pressing. SOLUTION: A powdery mixture is prepd. by mixing Al2 O3 of <2.0μm average particle diameter with 15-50vol.% metal boride, 5-25vol.% antioxidant of <=5.0μm average particle diameter for the metal boride based on the amt. of the metal boride and 0.05-2.0vol.% sintering aid based on the total amt. of the Al2 O3 and the metal boride. The mixture is compacted by cold isostatic pressing and the resultant compact is fired at <=1,900 deg.C in a nonoxidizing atmosphere to form a presintered compact, which is then subjected to hot isostatic pressing to obtain the objective Al2 O3 -metal boride sintered compact having >=99.5% relative density. |
