Abstract：Thermal barrier coatings (TBCs) is a crucial technique to improve the upper service temperature of titanium
alloy in aerospace field. In this paper, three kinds of TBCs were deposited on TA15 titanium alloy by atmospheric
plasma spraying process. The phase structure, microstructure and thermal shock life of coatings were investigated
for better understanding of the failure mechanism. The results show that T 'phase is formed in the assprayed
coating (c/( 2 a)≤1.01), and no phase transformation occurs during the thermal shock process. The thermal
shock life of GYYSZ /8YSZ composite coating is 2.6 times higher than that of single 8YSZ coating and 3
times higher than that of single GYYSZ coating. Mismatch of thermal expansion coefficient, low coating tensile
strength, and the formation of oxides on the surface of titanium matrix, result in the failure of TBCs.
2021, Vol. 31 
