The mechanical behavior of the fine-grained piezoelectric/substrate structure with multiple interface cracks under the electromechanical impact loading is investigated. Using the Laplace and Fourier integral transforms, the double-coupled singular integral equations and single-valued conditions of the problems are formulated. Both the singular integral equation and single-valued conditions are simplified into an algebraic equation through the Chebyshev point placement method and solved by numerical calculation. Then, the expression of the dynamic energy release rate is given with the help of the dynamic intensity factors of electric displacement and stress obtained. Finally, numerical results of the dynamic energy release rate with material parameters are demonstrated. The results show that the dynamic energy release rate depends on the size of the interface cracks, coating thickness, and the mechanical–electrical loading. Meanwhile, the fine-grained piezoelectric structures exhibit safer structural performance compared to normal one.

中文翻译：

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冲击载荷下细晶涂层复合结构多界面裂纹的瞬态响应

研究了具有多个界面裂纹的细晶粒压电/基底结构在机电冲击载荷下的力学行为。使用拉普拉斯和傅里叶积分变换，建立了问题的双耦合奇异积分方程和单值条件。通过切比雪夫点布置法将奇异积分方程和单值条件简化为代数方程并通过数值计算求解。然后，借助获得的电位移和应力的动态强度因子，给出了动态能量释放速率的表达式。最后，展示了动态能量释放率随材料参数的数值结果。结果表明，动态能量释放速率取决于界面裂纹的大小、涂层厚度和机电载荷。同时，与普通压电结构相比，细晶粒压电结构表现出更安全的结构性能。