PURPOSE: To obtain an alumina-zirconia sintered compact having enhanced toughness without reducing mechanical strength by incorporating high purity zirconia having a specified average grain diameter or below.
CONSTITUTION: A starting material mixture is prepd. by mixing 70-95wt.% Al2O3 powder with 30-5wt.% high purity ZrO, powder having ≤1μm particle diameter or further mixing 100 pts.wt. of the resulting mixture with 0.05-1 pt.wt. TiO2 powder. The starting material mixture is slurried by wet mixing and pulverization, a binder for compacting is added and powder for compacting is produced by drying. This powder is then compacted and fired to produce the objective high toughness alumina-zirconia sintered compact contg. high purity zirconia having ≤1μm average grain diameter and a zirconia crystal phase controlled so as to satisfy the relation of monoclinic zirconia/(monoclinic zirconia+tetragonal zirconia) ≥30% when expressed by intensity ratio by powder X-ray diffraction.
NONAKA HISAYOSHI
TAKETOMI TSUNEJI
Next Patent: JPS6116018