Liquid Phase Assisted Superplastic Deformation of TiO2-Doped ZTA Ceramics

Yufei Zu; Guoqing Chen; Xuesong Fu; Wenlong Zhou

doi:10.3390/ma12132050

Liquid Phase Assisted Superplastic Deformation of TiO₂-Doped ZTA Ceramics

Materials (Basel). 2019 Jun 26;12(13):2050. doi: 10.3390/ma12132050.

Authors

Yufei Zu^{1

2}, Guoqing Chen³, Xuesong Fu², Wenlong Zhou²

Affiliations

¹ Key Laboratory of Advanced Technology for Aerospace Vehicles of Liaoning Province, School of Aeronautics and Astronautics, Dalian University of Technology, Dalian 116085, China.
² Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085, China.
³ Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085, China. gqchen@dlut.edu.cn.

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 °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.

Keywords: TiO2 dopants; ZrO2 toughened Al2O3 ceramic; grain boundary feature; superplastic deformation.

Abstract

Grants and funding