Modeling and experimental characterization on temperature-dependent ferroelastic switching of 1–3 type piezocomposites

Abstract

Under high mechanical loading, 1–3 piezocomposites experience ferroelastic switching that causes depolarization. The combination of thermal and mechanical loads may affect the performance of 1–3 piezocomposites. A theoretical and experimental analysis has been carried out to study the ferroelastic behaviour of 1–3 piezocomposites under thermal load. Temperature dependent effective properties are determined analytically using equivalent layered approach and compared with the experimental values measured based on resonance technique. Experiments are conducted on poled piezocomposite samples subjected to large compressive stress, parallel to the fiber (poling) direction at elevated temperatures. A thermodynamically consistent uni-axial model is proposed to simulate the macroscopic behaviour of ferroelastic switching on piezocomposites. Volume fractions of three distinct uni-axial variants (instead of six variants) are used as internal variables, which describes the distribution of crystallographic orientation and polarization state of the crystal. Non-linear hardening parameter, based on gaussian function, is introduced to incorporate the grain boundary effects. The predicted effective properties are used in the uni-axial model and the classical stress versus strain and stress versus electrical displacement curves are simulated. Comparison between the experiments and simulations show that the proposed model can reproduce the characteristics of non-linear response. It is observed that the fiber volume fraction and temperature has a strong influence on the ferroelastic response of 1–3 piezocomposites.