Liquid Phase Assisted Superplastic Deformation of TiO(2)-Doped ZTA Ceramics

In this study, the compressive deformation of zirconia toughened alumina (ZTA) ceramics doped with different amounts of TiO(2) dopants were investigated in the temperature range of 1300–1400 °C to evaluate the stress exponent (n value) and apparent deformation activation energy (Q value). With 0–8 wt.% TiO(2) dopants, the n values and Q values of the TiO(2)-doped ZTA ceramics were calculated as 2–3 and 605–749 kJ/mol, respectively. Moreover, three grain boundary features were observed in these deformed materials, named the clean grain boundary, thin liquid phase grain boundary, and thick liquid phase grain boundary. Based on the deformation behavior and microstructure evolution, it was found that the lower apparent activation energy and higher strain rate of TiO(2)-doped ZTA ceramics are intensively related to the grain boundary feature.