Fabrication and Mechanical Properties of Yttria-doped Zirconia Ceramics Containing Alumina

Abstract

Metastable t-ZrO₂ solid solutions with the composition of ZrO₂/Y₂O₃/Al₂O₃=(74.25-71.25)/(0.75-3.75)/25 mol% crystallize at 780°-860°C from amorphous materials prepared by the simultaneous hydrolysis of zirconium, yttrium and aluminum acetylacetonates. Two kinds of materials are fabricated by hot isostatic pressing for 1 hat 1130°and 1230°C under 196 MPa: (i) perfect ZrO₂ solid solution ceramics and (ii) composites of ZrO₂ solid solution and α-Al₂O₃. Mechanical properties are examined in connection with the microstructures and t/m ratios.