Fatigue crack analysis in piezoelectric specimens by a single-domain BEM

In this paper, the fatigue crack problems in piezoelectric materials under cyclic mechanical loading or alternating electric field were analyzed by a single-domain boundary element method. To determine the direction of the crack propagation, the fracture criteria of maximum of hoop mechanical strain energy release rate was used. Meanwhile, for evaluating the remaining life of the cracked piezoelectric specimens, the Paris-type laws based on different fracture parameters were employed and compared. All the involved fracture parameters were computed by the interaction integral method. Numerical examples were considered and analyzed for cyclic mechanical and electrical loadings, respectively. The comparisons showed the efficiency of the present BEM program in analyzing fatigue cracks and the choice of the effective fracture parameter in Paris' law for life prediction.