Abstract: Composite ceramics having a high strength, a high toughness and an excellent abrasion resistance, and a method of producing the same. The composite ceramics comprises 10 to 30 mass % of a zirconia crystal phase including Ce-stabilized zirconia crystal particles which contain CeO2 in an amount of 9 to 12 mol % and Y-stabilized zirconia crystal particles which contain Y2O3 in an amount of 2.8 to 4.5 mol %; and 70 to 90 mass % of an alumina crystal phase, the zirconia crystal phase having an average crystal particle size of not larger than 1 ?m.

Abstract: A composite ceramic of the present invention includes granular alumina particles (A) having an aspect ratio of 3 or less, granular zirconia particles (B) having an aspect ratio of 3 or less, and a columnar crystal (C) having an aspect ratio of 3 or more, the columnar crystal including a complex metal oxide containing an alkaline-earth metal element and aluminum element. The composite ceramic has high flexural strength, toughness, and hardness, and achieves excellent hot-water resistance and high flexural strength after hydrothermal degradation resistance test.

Abstract: Alumina/zirconia ceramics containing Al2O3 in an amount of not less than 65 mass % and ZrO2 in an amount of 4 to 34 mass %, and further containing TiO2, MgO and SiO2. The ceramics effectively suppresses the growth of shape isotropic particles of alumina, suppresses the growth of zirconia particles, and has a high strength and a high hardness. Besides, the ceramics containing SrO features a high fracture toughness.

Abstract: Composite ceramics having a high strength, a high toughness and an excellent abrasion resistance, and a method of producing the same. The composite ceramics comprises 10 to 30 mass % of a zirconia crystal phase including Ce-stabilized zirconia crystal particles which contain CeO2 in an amount of 9 to 12 mol % and Y-stabilized zirconia crystal particles which contain Y2O3 in an amount of 2.8 to 4.5 mol %; and 70 to 90 mass % of an alumina crystal phase, the zirconia crystal phase having an average crystal particle size of not larger than 1 ?m.

Abstract: Composite ceramics having a high strength, a high toughness and an excellent abrasion resistance, and a method of producing the same. The composite ceramics comprises 10 to 30 mass % of a zirconia crystal phase containing 9 to 12 mol % of CeO2 and 2.8 to 4.5 mol % of Y2O3; and 70 to 90 mass % of an alumina crystal phase, the zirconia crystal phase having an average crystal particle size of not larger than 1 ?m.

Abstract: Alumina/zirconia ceramics containing Al2O3 in an amount of not less than 65 mass % and ZrO2 in an amount of 4 to 34 mass %, and further containing TiO2, MgO and SiO2. The ceramics effectively suppresses the growth of shape isotropic particles of alumina, suppresses the growth of zirconia particles, and has a high strength and a high hardness. Besides, the ceramics containing SrO features a high fracture toughness.