ZrO2 based ceramic material and method of producing the same

摘要

A ZrO2 based ceramic material having excellent mechanical strength and fracture toughness comprises a first phase of ZrO2 grains containing CeO2 as a stabilizer and having an average grain size of 5 mu m or less, a second phase of Al2O3 grains having an average grain size of 2 mu m or less, and a third phase of elongated crystals of a complex oxide of Al, Ce, and one of Mg and Ca. At least 90 vol% of the first phase is composed of tetragonal ZrO2. An aluminum (Al) content in the ceramic material is determined such that when Al of the complex oxide is converted to Al2O3, a total amount of Al2O3 in the ceramic material is within a range of 0.5 to 50 vol%. A content of the third phase in the ceramic material is determined within a range of 0.5 to 5 by area%. It is preferred that fine Al2O3 grains having an average grain size of 1 mu m or less of the second phase are dispersed within the ZrO2 grains at a dispersion ratio of at least 2%. <IMAGE>