Polarization switching responses of 1-3 and 0-3 active composites

This study presents simplified micromechanical models for estimating the overall polarization switching hysteretic responses of active composites comprising of ferroelectric ceramics (active constituent) and inactive constituent. A nonlinear rate-dependent constitutive model for describing hysteretic polarization and butterfly strain responses is used for the ferroelectric constituent, while the inactive constituent is assumed to experience elastic or viscoelastic response. Two unit-cell models with four and eight subcells are considered to determine the overall responses of 1-3 and 0-3 active composites, respectively. Linearized micromechanical relations are used to provide trial values of the overall electro-mechanical responses, and a fixed point iterative method is then used in order to correct errors from linearizing the nonlinear responses. The micromechanical predictions of 1-3 active composites are validated with experimental data available in literature. Parametric studies are conducted to illustrate the effects of microstructural geometries and volume contents of the ferroelectric inhomogeneity as well as loading history on the overall hysteretic responses of active composites.