Phase Field Simulation of Ferroelectrics with Cracks

Abstract

By employing a dipole defect model, two-dimensional phase field simulations of domain switching in the crack tip vicinity of a crack embedded in a relaxor ferroelectric single crystal, which was subjected to mechanical loading and electric field, have been carried out. The interaction between the dipole defects and crack, the influence of the dipole defect concentration density on the switching process, and the coupling effect of mechanical stress and electric field on domain switching in the vicinity of the crack tip have been studied. Comparing the results obtained from relaxor ferroelectrics with those of normal ferroelectrics, the former showed that, due to the interaction between the dipole defects and crack, polarization switching in the vicinity of the crack tip was suppressed. Moreover, the coupling between applied mechanical stress and electric field can either promote or suppress domain switching in the vicinity of a crack.