Elinvar-Like Effect Induced by High Lattice Distortion in Zr6Ta2O17 Ceramics
Xiaopeng Hu,
Qing Liu,
Sai Liu,
Yu Zou,
Jinwei Guo,
Junyao Wu,
Wang Zhu,
Zengsheng Ma
Affiliations
Xiaopeng Hu
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Qing Liu
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Sai Liu
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Yu Zou
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Jinwei Guo
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Junyao Wu
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Wang Zhu
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Zengsheng Ma
Key Laboratory of Key Film Materials & Application for Equipment (Hunan province), School of Materials Science and Engineering,
Xiangtan University, Xiangtan, Hunan 411105, China.
Super strength and toughness, excellent deformation resistance, and high-temperature service performance are the key factors to determine the practical application of new thermal barrier coatings (TBCs). The limited mobility of dislocations and the internal inherent defects in ceramics will inevitably lead to the decline of strength–plasticity and the reduction of service performance. Introducing preexisting twin boundaries and stacking faults (SFs) or preparing ceramic materials with high configuration entropy has demonstrated to be an effective strategy for enhancing the mechanical properties of ceramics. However, due to the positive thermal expansion coefficient of most ceramics and the remarkable increase of structural disorder at elevated temperature, the problem of elastic softening has become a bottleneck restricting the high-temperature service life of new TBCs. In this paper, the deformation behavior of high configuration entropy Zr6Ta2O17 ceramics at 25 to 1,200 °C was in situ monitored via digital image correlation technique and three-point bending test platform in high-temperature environment. A remarkable Elinvar-like effect appears in the Zr6Ta2O17 ceramic. More interestingly, mechanical deformation dominates the severe lattice distortion (deformation twins, SFs) and the disorder–order transition of chemical order at the atomic scale, while temperature can further enhance the degree of lattice distortion and ordering of Zr6Ta2O17 ceramics. Furthermore, the atomic fluctuations at high temperature promotes the comprehensive improvement of mechanical properties in the Zr6Ta2O17 ceramics.
