ALUMINA-ZIRCONIA COMPOSITE SINTERED PRODUCT AND METHOD FOR MAKING THE SAME

摘要

An alumina-zirconia composite sintered product which comprises a zirconia crystalline phase composed mainly of a tetragonal zirconia and an alumina crystalline phase is described. The sintered product has such a fine structure that regions of said alumina crystalline phase being separated with the zirconia crystalline phase at a size of from 0.1 to 2 .mu.m on average. Preferably, the zirconia crystalline phase contains not larger than 4 mol% of yttrium oxide or not larger than 14 mol% of cerium oxide as a stabilizer. A method for making a starting composite powder and a method for making a composite sintered product using the composite powder are also described.