Processing of nano-Y-TZP/Al₂O₃ composites. I: Preparation and characterization of nano-Y-TZP/Al₂O₃ composite powders

Nano-sized and well dispersed Y-TZP/alumina (Y-TZP-rich) composite powders have been prepared via a chemical method. It has been found that alumina exists metastably in the Y-TZP lattice in the composite powders at relatively low temperatures before the crystallization of α-alumina from the composites started at around 1200 °C. Alumina in the composite powders impedes the crystallite growth of Y-TZP and increases the specific surface area of the composite powders. This effect is discussed and attributed to the lattice distortion of Y-TZP by alumina.