Studies on rate-dependent switching effects of piezoelectric materials using a finite element model

The main goal of this paper consists in the modeling of rate-dependent behavior of piezoelectric materials within a three-dimensional finite element setting. We propose a rate-dependent polarization framework which is applied to cyclic electrical loading at various frequencies. The reduction in free energy of a grain is used as a criterion for the onset of the domain switching process. Nucleation in new grains and propagation of the domain walls during domain switching is modeled by a linear kinetics theory. Averaging over all individual grains renders the macroscopic response of the bulk material. Intergranular effects, which are essential for realistic simulations, are phenomenologically captured via a probabilistic approach. The presented numerical examples, as based on the proposed three-dimensional finite element framework, are related to the simulation of PIC-151 ceramics. In particular, averaged electric displacement versus electric field curves are plotted and compared with experimental data reported in the literature.