Studies on crystallization behaviour of 3Y-TZP/Al2O3 composite powders

The present work deals with the characterization of 3.0 mol.% yttria stabilized zirconia (3Y-TZP) powders prepared as composite precursors containing up to 20.0 vol.% of alumina. Following the wet-chemistry route of co-precipitation, a homogeneous dispersion of component hydroxides was obtained. Effect of calcination treatment on t-phase and primary particle size evolution of zirconia was investigated by XRD technique. A marked difference with respect to inhibition of crystallization reaction of 3Y-TZP was observed in the presence of alumina. This is attributed to the increased diffusion lengths of the two developing phases. The powders could be retained in the ultrafine and quasi-amorphous state by a suitable choice of alumina content and calcination treatment.