Analysis of a subinterface crack in piezoelectric bimaterials with the extended finite element method

In this work, a subinterface crack problem in piezoelectric bimaterials is analyzed by the extended finite element method (XFEM). Associated with the level set method, the XFEM enables us to accurately capture the singularities at the crack-tips. The fracture parameters consisting of the mechanical stress intensity factors and the electrical displacement intensity factor are evaluated by using the asymptotic crack-tip fields derived from the generalized Stroh's formalism and the interaction integral. Numerical examples for an electrically impermeable subinterface crack are presented and discussed to reveal various aspects including the effects of the crack distance to the interface, the crack inclination, the poling direction, the loading conditions, the basis enrichment functions, the enrichment strategies, the domain of the J-integral computation, etc. on the field intensity factors. Convergence study in the energy norm and in the intensity factors is additionally presented. To assess the accuracy of the proposed approach, the results obtained by the XFEM are compared with the analytical reference solutions available in the literature and excellent agreements are found.