Indexed by:Journal Papers

Date of Publication:2019-07-01

Journal:MATERIALS

Included Journals:SCIE、EI、PubMed

Volume:12

Issue:13

ISSN No.:1996-1944

Key Words:ZrO2 toughened Al2O3 ceramic; grain boundary feature; superplastic deformation; TiO2 dopants

Abstract:In this study, the compressive deformation of zirconia toughened alumina (ZTA) ceramics doped with different amounts of TiO2 dopants were investigated in the temperature range of 1300-1400 degrees C to evaluate the stress exponent (n value) and apparent deformation activation energy (Q value). With 0-8 wt.% TiO2 dopants, the n values and Q values of the TiO2-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 TiO2-doped ZTA ceramics are intensively related to the grain boundary feature.