Preparation, sintering, microstructure, and thermal stability of Y2O3- and CeO2-doped tetragonal zirconia ceramics

Yttria- and ceria-doped tetragonal zirconia polycrystals ((Y, Ce)-TZP) with compositions 2·5 mol% YO_1·5-4 mol% CeO₂---ZrO₂, 4 mol% YO_1·5-4 mol% CeO₂---ZrO₂, and 2·5 mol% YO_1·5-5·5 mol% CeO₂---ZrO₂ were prepared from zirconia sols obtained hy hydrolysis of ZrOCl₂ solution, and their sintering, microstructure and thermal stability were studied. Sintered bodies with 99% TD were obtained by firing at 1400°C for 2 h in air. The grain size of (Y, Ce)-TZP increased with decreasing Y₂O₃ content in Y₂O₃---CeO₂---ZrO₂. (Y, Ce)-TZP was resistant to tetragonal-to-monoclinic (t → m) phase transformation during low temperature ageing as compared with 3Y-TZP.