Microstructure and mechanical properties of ZrO_2 ceramics toughened by 5-20 vol% Ta metallic particles fabricated by pressureless sintering

摘要

ZrO_2bascd composites toughened by 5, 10, 15 and 20 vol% lamellar shape Ta metallic particles were made by pressureless sintering. The microstructure and mechanical properties of these novel ceramic-metal composites have been studied. With only 15 vol%, the toughness of ZrO_2-Ta composites was increased from 9.1 of monolithic zirconia to 14 MPa m~(1/2) and the average bend strength was 700 MPa. Our results have demonstrated that zirconia transformation and ductile phase toughening concepts can get together to enhance the fracture toughness of zirconia-based materials with high strength.