Abstract:With the increase of operating temperature in aero-engine turbine blades, a vitreousSmaterial (CMAS) consisting mainly of CaO, MgO, Al2O3 and SiO2 were increasingly harmful to the thermal barrier coatings deposited on the blade. Therefore, the performance and durability of thermal barrier coatings should meet higher requirements. In this study, the influence of CMAS penetration on interfacial crack propagation and residual stress in the electron beam physical vapor deposition thermal barrier coatings was investigated by using finite element method. The sinusoidal curves with fixed wavelength and varying amplitude were used to model the interfaces with different roughness. At the same time, the effect of the elastic modulus of CMAS and the interaction between interface morphology and CMAS were taken into account. The results show that the increase of CMAS elastic modulus has an inhibitory effect on interfacial cracks, and the smaller the TGO amplitude and thickness, the more obvious the inhibition. There is a critical point for the effect of CMAS elastic modulus on the maximum residual stress S22 in top coat (TC) layer. Before the critical point, the change of CMAS elastic modulus has a greater influence on the maximum residual stress of TC layer, and with the increase of elastic modulus of CMAS, the maximum residual stress of TC layer decreases greatly; after the critical point, the maximum residual stress of TC layer is hardly affected by the change of elastic modulus of CMAS. These results are of great significance for the study of the failure mechanism of thermal barrier coatings by electron beam physical vapor deposition, it can provide guidance for the optimization of the interface of thermal barrier coatings.