Kinetics of hydrothermally induced transformation of yttria partially stabilized zirconia

Yttria-stabilized zirconia undergoes tetragonal to monoclinic phase transformation under hydrothermal conditions in the temperature range of 150–350 °C. Phase transformation accompanied by volume change in bulk yttria partially stabilized zirconia (YPSZ) leads to micro-cracking, loss of mechanical integrity and ultimately disintegration. The mechanical properties of the bulk YPSZ material deteriorate with the amount of the phase transformation and in some cases catastrophic failure are observed. The phase transformation is analyzed using macroscopic and microscopic techniques. X-ray diffraction data is used to quantify the phase transformation in bulk material. Kinetics of the phase transformation is studied at various temperatures.