An energy-based model for ferroelectric ceramics

Abstract

From the basic physical insight, the configuration and switching process of ferroelectric domains are both governed by energetic principles. Based on these energetic principles, a model for the nonlinear hysteretic behaviour of ferroelectric ceramics is developed. It relies on an energy-consistent thermodynamic formulation, based on two constitutive functions: free energy and dissipation. The model is grounded on an energy balance where the free energy and dissipation are known at all times during the polarisation process due to the incremental formulation obtained. All internal variables arise from the minimisation of a thermodynamic potential. Experimental measurements are performed in order to identify the parameters of the model and to validate the evolution of internal parameters generated by the energy-based model for different cases of loading. It is notably shown that the model allows capturing the energy losses under varying electrical loadings, which can be a key to the prediction of functional fatigue.