A statistical model for predicting effective electroelastic properties of polycrystalline ferroelectric ceramics with aligned defects

This work is focused on the analysis of the effects of domain switching and defects on the effective electroelastic properties of polycrystalline ferroelectric ceramics. On the basis of experimental results and the classical nucleation theory, a statistical micromechanics model is developed in order to describe the microstructural evolution of polycrystalline ferroelectric ceramics. Further, the methods of Eshelby's equivalent inclusion and Mori-Tanaka's mean field theory are used to predict the effective electroelastic properties of polycrystalline ferroelectric ceramics with aligned defects, taking the effects of the shapes of individual crystal and defect into consideration. Some numerical results for BaTiO3 polycrystalline ceramics with aligned defects are carried out in order to illustrate the effects of the domain switching and defects on the effective electroelastic properties of polycrystalline ferroelectric ceramics. It has been shown that the simulations are in good agreement with the experimental results. (C) 2000 Elsevier Science Ltd. All rights reserved.