Abstract
In this paper, a finite element program in conjunction with domain switching criterion was developed to analyze domain wall switching and its effect on the near tip stress field in piezoelectric materials containing a crack. Domain switching zones in the vicinity of the crack tip corresponding to various combined electric and mechanical loads were obtained. It is found that the size, shape and mode (90° or 180° switching) of domain switching zone near the crack tip depend on the direction as well as magnitude of the applied electric field. For a positive electric field (same as the poling direction), 90° domain switching occurs behind the crack tip, and the zone increases as the applied positive electric field increases. If the applied electric field is negative, then a 180° domain switching zone appears ahead of the crack tip while a 90° domain switching zone exists behind the tip. Moreover, the stress field near the crack tip is found to be significantly affected by the domain switching.
