Microcracking damage analysis in piezoelectric bimaterial solids

With the increasing use of piezoelectric materials, the damage evaluation for such materials has been a hot topic in fracture mechanics. This paper is devoted to investigate the subinterface microcracking damage problems in piezoelectric bimaterial solids. After deriving the elementary solution for an edge dislocation near the interface, the strong interaction problem of multiple subinterface microcracks is reduced to a system of singular integral equations by using the superimposition method. With the aid of the solution for this system, which is obtained using the Chebyshev numerical integral technique, such crack tip fracture parameters as the stress intensity factors, the electric displacement intensity factor and the mechanical strain energy release rate are easily evaluated. Based on these, path-independent integral analyses are performed by adopting the J-integral and the M-integral. The numerical results show that the M-integral is sensitive to modifications of the remote electric loading and microcrack configuration, and provides a natural description of the growth and nucleation of microcracks below the interface of piezoelectric bimaterial solids. This fully proves that the M-integral actually provides a powerful tool for evaluating stationary or evolutionary microcracking damages in piezoelectric bimaterial solids.