On phase transformations and intelligent behavior of ferroelectric crystals

Abstract

Ferroelectric crystals possess memory functions in their thermal, mechanical, electric and optic properties due to the ferroelectric-paraelectric phase transformation. The dependence of the transformation temperature upon the applied electric fields and mechanical loads renders these crystals desirable materials for the design of smart sensors and actuators. A continuum model for predicting this behavior is proposed. The analysis indicates that the stress dependence of the transformation is determined by the lattice distortion of the crystal associated with the corresponding structural transformation. Some of the predictions are in qualitative agreement with experimental observation.