Abstract: The present invention produces a zirconia-alumina composite ceramic material that exhibits an excellent wear resistance and hardness and that resists chipping at the particle edges. The zirconia-alumina composite ceramic material according to the present invention has a composite structure in which zirconia particles are dispersed in alumina particles and the alumina particles are dispersed in the zirconia particles. A first phase is formed of ceria-containing zirconia particles and a second phase is formed of alumina particles. An ?-alumina powder having an average particle size of at least 0.1 ?m and a ?-alumina powder having an average particle size of 0.01 to 0.1 ?m are used in a proportion of 85:15 to 65:35 as the mass ratio for the alumina powder for producing the alumina particles of the second phase.

Abstract: A ZrO2—Al2O3 composite ceramic material having excellent wear resistance, hardness, strength and toughness is provided. This ceramic material comprises a ZrO2 phase composed of 90 vol % or more of tetragonal ZrO2, and containing 10 to 12 mol % of CeO2 as a stabilizer, and an Al2O3 phase. An amount of the Al2O3 phase in the ceramic material is in a range of 20 to 70 vol %, and preferably 40 to 70 vol %. In the composite ceramic material, Al2O3 grains each having a fine ZrO2 grain therein are dispersed. Some of the Al2O3 grains each having the fine ZrO2 grain therein are trapped within ZrO2 grains to form composite grains. A ratio of the number of the Al2O3 grains each having the fine ZrO2 grain therein relative to the number of the entire Al2O3 grains dispersed in the composite ceramic material is 10% or more, and preferably 50% or more.

Abstract: A ZrO2—Al2O3 composite ceramic material having excellent wear resistance, hardness, strength and toughness is provided. This ceramic material comprises a ZrO2 phase composed of 90 vol % or more of tetragonal ZrO2, and containing 10 to 12 mol % of CeO2 as a stabilizer, and an Al2O3 phase. An amount of the Al2O3 phase in the ceramic material is in a range of 20 to 70 vol %, and preferably 40 to 70 vol %. In the composite ceramic material, Al2O3 grains each having a fine ZrO2 grain therein are dispersed. Some of the Al2O3 grains each having the fine ZrO2 grain therein are trapped within ZrO2 grains to form composite grains. A ratio of the number of the Al2O3 grains each having the fine ZrO2 grain therein relative to the number of the entire Al2O3 grains dispersed in the composite ceramic material is 10% or more, and preferably 50% or more.

Abstract: A ZrO2—Al2O3 composite ceramic material having excellent wear resistance, hardness, strength and toughness is provided. This ceramic material comprises a ZrO2 phase composed of 90 vol % or more of tetragonal ZrO2, and containing 10 to 12 mol % of CeO2 as a stabilizer, and an Al2O3 phase. An amount of the Al2O3 phase in the ceramic material is in a range of 20 to 70 vol %, and preferably 40 to 70 vol %. In the composite ceramic material, Al2O3 grains each having a fine ZrO2 grain therein are dispersed. Some of the Al2O3 grains each having the fine ZrO2 grain therein are trapped within ZrO2 grains to form composite grains. A ratio of the number of the Al2O3 grains each having the fine ZrO2 grain therein relative to the number of the entire Al2O3 grains dispersed in the composite ceramic material is 10% or more, and preferably 50% or more.

Abstract: A ZrO2—Al2O3 composite ceramic material having excellent wear resistance, hardness, strength and toughness is provided. This ceramic material comprises a ZrO2 phase composed of 90 vol % or more of tetragonal ZrO2, and containing 10 to 12 mol % of CeO2 as a stabilizer, and an Al2O3 phase. An amount of the Al2O3 phase in the ceramic material is in a range of 20 to 70 vol %, and preferably 40 to 70 vol %. In the composite ceramic material, Al2O3 grains each having a fine ZrO2 grain therein are dispersed. Some of the Al2O3 grains each having the fine ZrO2 grain therein are trapped within ZrO2 grains to form composite grains. A ratio of the number of the Al2O3 grains each having the fine ZrO2 grain therein relative to the number of the entire Al2O3 grains dispersed in the composite ceramic material is 10% or more, and preferably 50% or more.

Abstract: A ZrO2—Al2O3 composite ceramic material having excellent wear resistance, hardness, strength and toughness is provided. This ceramic material comprises a ZrO2 phase composed of 90 vol % or more of tetragonal ZrO2, and preferably containing 10 to 12 mol % of CeO2 as a stabilizer, and an Al2O3 phase. An amount of the Al2O3 phase in the ceramic material is in a range of 20 to 70 vol %. The ceramic material comprises composite particles dispersed therein, each of which has a triple nanocomposite structure that an Al2O3 grain containing a fine ZrO2 grain therein is trapped within a ZrO2 grain.