Preparation and Mechanical Properties of Zirconia Ceramics Doped with Different Y2O3 Contents

The sintering behavior and mechanical properties of zirconia doped with 2.0mol%-3.0mol%Y2O3were studied by pressure-less sintering. The experimental results show that the densification temperature of zirconia ceramics increases gradually with the decrease of Y2O3doping content by which decreases the sintering driving force due to the lower oxygen vacancy concentration of the systems. Furthermore, the bending strength and fracture toughness of the prepared zirconia ceramics increase with the decrease of Y2O3doping content. It can be attributed to the fact that the phase stability of tetragonal zirconia decreases with the decrease of Y2O3doping content, which is easier to induce "phase transformation toughening" and dissipate impact energy. The relative density, bending strength and fracture toughness of 2.0 mol% Y2O3doped zirconia ceramics(2.0Y-ZrO2)sintered at 1 525 ℃ are 99.00%, 1 256.65±20.82 MPa and 9.85±0.13 MPa·m1/2, respectively.