中文摘要：

The different temperature-induced nonlinear behavior near a conducting crack tip in a ferroelectric single crystal is studied based on a phase field approach containing the time-dependent Ginzburg-Landau equation.Since domain switching in a crack tip plays an important role in the fracture behavior,by using three-dimensional nonlinear finite element method,the temperature-induced domain switching behavior of a ferroelectric single crystal is simulated under applied electrical and mechanical loads.The simulations show that increasing the temperature will enhance the crack propagation under a strong electric field,which results in switching-weakening.In particular,increasing the temperature from 300°C to 600°C will impede the crack propagation under combined mechanical and electric field loading,which results in switching-toughening.Salient features of the results are consistent with many experimental observations.

英文摘要：

The different temperature-induced nonlinear behavior near a conducting crack tip in a ferroelectric single crystal is studied based on a phase field approach containing the time-dependent Ginzburg-Landau equation. Since domain switching in a crack tip plays an important role in the fracture behavior, by using three-dimensional nonlin- ear finite element method, the temperature-induced domain switching behavior of a ferroelectric single crystal is simulated under applied electrical and mechanical loads. The simulations show that increasing the temperature will enhance the crack propagation under a strong electric field, which results in switching-weakening. In particular, increasing the temperature from 300 ℃ to 600 ℃ will impede the crack propagation under combined mechanical and electric field loading, which results in switching-toughening. Salient features of the results are consistent with many experimental observations.