Several embedded cracks in a functionally graded piezoelectric strip under dynamic loading

This paper deals with the fracture analysis of multiple cracks in a functionally graded piezoelectric (FGP) layer under applied anti-plane time-harmonic mechanical and in-plane electrical loading within the framework of linear electro-elasticity. The analysis is based on the stress and electric fields caused by Volterra-type screw dislocation in the medium. The crack surfaces are assumed to be impermeable condition. The material properties of the medium are considered to obey exponential variations. In order to model the cracked layer, the distributed dislocation technique is employed to perform Cauchy-type singular integral equations for layer, in which the unknown variables are dislocation densities. The dislocation densities are then employed to derive field intensity factors at the crack tips. The results show that the stress and the electric displacement intensity factors at the crack tips depend on the cracks configuration, frequency and material properties. Finally, several numerical examples are solved to obtain the dynamic stress intensity factors (DSIFs) and electric displacement intensity factors.