Formation and Sintering of Yttria‐Doped Tetragonal Zirconia with 50 mol% Alumina Prepared by the Hydrazine Method

Abstract

Al2O3/Y2O3‐doped ZrO2 composite powders with 50 mol% Al2O3 are prepared by the hydrazine method. As‐prepared powders are mixtures of AlO(OH) gel and amorphous ZrO2 solid solutions containing Y2O3 and Al2O3. The formation process leading to α‐Al2O3‐t‐ZrO2 composite powders is examined. Hot isostatic pressing is performed for 2 h at 1400°C under 196 MPa using θ‐Al2O3‐t‐ZrO2 composite powders. The resulting dense, sintered α‐Al2O3‐t‐ZrO2 composites show excellent mechanical strength.