ALUMINA-ZIRCONIA-SILICON CARBIDE COMPOSITE SINTERED BODY HAVING HIGH STRENGTH, TOUGHNESS AND HARDNESS

摘要

PURPOSE:To obtain the titled composite sintered body having superior strength, toughness, hardness and thermal shock resistance by molding a powdery mixture of partially stabilized zirconia with SiC whiskers and powdery stating material for alumina and sintering the molded body optionally under pressure. CONSTITUTION:A powdery mixture is obtd. by mixing =55vol.% in total of 5-50vol.% partially stabilized zirconia having 0.1-1.0mum average particle size and =30m2/g BET specific surface area and 3-40vol.% SiC whiskers having =1mum diameter and 3-200 aspect ratio with =45vol.% powdery starting material for alumina having =50m2/g BET specific surface area and =99% purity and a mixing medium such as ethanol by means of a ball mill. The mixture is molded and the molded body is sintered at 1,400-1,700 deg.C optionally under pressure to obtain an alumina-zirconia-SiC composite sintered body having =99% relative density and 0.3-0.5mum grain size.