The stress intensity factors of slightly undulating interface cracks of anisotropic bimaterials

Summary An interface crack in anisotropic dissimilar materials is treated here as a slightly undulating one. Based on Lekhnitskii-Eshelby-Stroh (LES) representation and perturbation analysis, analytic solutions are given for displacement and stress fields of both anisotropic half-planes. Many failures, e.g., occurring in the interfaces between thin-film and substrate or fiber and matrix, are always slightly undulating. For these reasons, the unevenness effect of crack faces must be taken into account to determine the practical stress intensity factors for predicting the interface fracture behaviours. And the solutions to the first order of unevenness are determined by considering only the lateral stresses, because other far-field stresses have dominated the zeroth order solution.