Coating often plays a role in monitoring and protecting substrates in engineering applications. Interface cracks between the coating and the substrate can lead to crack growth under the action of external loading and will cause device failure. In this paper, the behavior of a fine-grained piezoelectric coating/substrate with a Griffith interface crack under steady-state thermal loading is studied. The temperature field, displacement field, and electric field of the coupling of thermal and electromechanical problems are constructed via integral transformation and the principle of superposition. Thus, problems are transformed into a system of singular integral equations, and the expressions of thermal intensity factor, thermal stress intensity factor, and electric displacement intensity factor are obtained. We used a numerical calculation and a system of singular equations to obtain the relationship of strength factor with material parameters, coating thickness, and crack size.

中文翻译：

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细粒压电涂层/基体在热载荷下格里菲斯界面裂纹的断裂分析

在工程应用中，涂层通常在监视和保护基材方面发挥作用。涂层和基材之间的界面裂纹会在外部载荷的作用下导致裂纹扩展，并会导致器件故障。本文研究了在稳态热负荷下具有格里菲斯界面裂纹的细粒度压电涂层/基底的行为。通过积分变换和叠加原理构造了热力与机电问题耦合的温度场，位移场和电场。因此，将问题转化为奇异积分方程组，并获得热强度因子，热应力强度因子和电位移强度因子的表达式。