HIGH-STRENGTH, HIGH-HARDNESS ALUMINA CERAMICS AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To inexpensively provide an alumina ceramic having both of high strength and high hardness. SOLUTION: This alumina ceramic comprises 0.5-12 wt.% of YAG particles and the balance of substantially alumina. The average crystal particle size of the YAG particles is adjusted to 0.05-1.5 μm, while the average particle size of the alumina is controlled to 0.5-5.0 μm and the YAG grains are dispersed both on the grain boundaries in the sintered product and in the alumina particles whereby the objective alumina ceramic is constituted.