Bending fracture behavior of freestanding (Gd0.9Yb0.1)2Zr2O7 coatings by using digital image correlation and FEM simulation with 3D geometrical reconstruction

• Main Authors: Weiguo Mao, Yujie Wang, Jun Shi, Huiyu Huang, Yuncheng Wang, Liang Lv, Haoyong Yang, Chen Zou, Cuiying Dai, Xiaolei Zhu, Daining Fang
• Format: Article
• Language: English
• Published: SpringerOpen 2019-12-01
• Series: Journal of Advanced Ceramics
• Subjects: thermal barrier coating; X-ray computed tomography; bending fracture; geometrical reconstruction; cracking strain
• Online Access: https://doi.org/10.1007/s40145-019-0340-6

Abstract It is important to investigate the mechanical performances of (Gd0.9Yb0.1)2Zr2O7 (GYbZ) materials deposited on irregular substrates for improving new thermal barrier coatings. Three-point bending fracture characteristics of freestanding GYbZ coating prepared by supersonic plasma sprayed (SPS) technique were investigated with the help of digital image correlation technique. The cracking time, crack propagation path, and mechanical properties of GYbZ coating were obtained. Meanwhile, the X-ray computed tomography technique was introduced to scan the microstructure of freestanding GYbZ coatings, which are used to establish three-dimensional (3D) finite element model by using the Avizo software. The brittle cracking criterion was applied to describe the bending fracture process of GYbZ coatings. The critical cracking strain was estimated as 0.36%±0.03% by repeatedly comparing the difference between the experimental and simulated curves. The results would be extended to predict the dangerous region and failure mechanisms of GYbZ coatings deposited on irregular substrate during finite element simulations.