A SIMPLIFIED MODEL FOR DOMAIN SWITCHING OF FERROELECTRIC CRYSTAL

I. INTRODUCTION Domain switching is the main source of nonlinear characteristics of ferroelectric materials. The trans-formation performance of domain is the basis for ferroelectric constitutive research. In many literatures1??10], complete switching models were adopted, in which ferroelectric materials are considered tobe consist of several basic sorts of domains, which are independent of each other. Under the actionof su?ciently strong electric ?elds or mechanical stress, the orienta…

A Simplified Model for Domain Switching of Ferroelectric Crystal

Domain switching is the main source of nonlinear characteristics in ferroelectrics. According to crystal plasticity theory, the domains and domain switching systems for perovskite- type structure ferroelectrics are de?ned. Considering the traverse motion performance of domain wall, a rather simpli?ed form of evolution law about incremental of volume fraction during domain switching has been developed. The main factors, which exert an in?uence on domain switching, such as material parameters, domain wall motion history, kind of domain switching (180? or 90?) and volume fraction, could be addressed. The hysteresis loops of spontaneous electric polarization as a function of electric ?eld, the butter?y shaped strain versus electric ?eld curve and the platform relations between spontaneous polarization and stress, as well as the longitudinal strain and stress, are well simulated and discussed.