Microstructural Coarsening of Zirconia-Toughened Alumina Composites

In this work, the microstructural coarsening induced by heat treatment at temperatures between 1450° and 1750°C, for different zirconia-toughened alumina (ZTA) materials has been studied. In doing so, grain growth kinetics and fracture toughness have been documented and analyzed. Obtained results are discussed and rationalized in terms of microstructural effects on zirconia clustering and transformability (content and size) and operative toughening mechanisms. Based on the relatively broad microstructural and toughness ranges exhibited by the ZTA composites developed and characterized, it is concluded that fracture toughness tailoring through microstructure control may be effectively implemented for these materials.