To analyze an interface crack in a piezoelectric material, a program has been developed in this study. The program can be used for calculating the stress and electric displacement intensity factors employing the J based mutual integral. This program is able to separate each mode of the stress and electric displacement and to calculate J integral for the finite-sized specimen where the analytic solutions are hardly obtained.
Using the coded program, the stress and electric displacement intensity factors for an interfacial crack in finite sized piezoelectric bimaterials is obtained. In the structure used in numerical calculation, transversely isotropic materials are chosen and the isotropic planes of two materials are joined together. Materials such as PZT4, PZT5H and PZT7A are selected for FEM analysis. As the load on the boundary increases, the stress intensity factors, k1 and k2, increase but the electric displacement intensity factor, k4, decreases. And the magnitude of the stress and electric displacement intensity factors changes according to the direction of the electric field. The effect of the specimen size and crack length on intensity factors is also investigated in this study.
