Evolution of Linear Moduli and Remanent State Variables during Polarization Reversal in a Lead Zirconate Titanate Wafer at Various Temperatures

A poled lead zirconate titanate (PZT) wafer is subjected to electric field loading of pulse type whose magnitude is increasing until polarization direction is completely reversed. Then it is subjected to the same type of electric field loading in the opposite direction to return to initial state. During the complete cycle of polarization reversal, electric displacement in thickness direction and in-plane strain are measured in both loaded and unloaded states. The same measurement is made at four different temperatures. From the measured data, permittivity and piezoelectric coefficient are evaluated and fitted as linear functions of remanent polarization and temperature. Reference remanent polarization-reference remanent in-plane strain plots are drawn and switching processes at different temperatures are compared with each other. The present observations will be helpful in constructing constitutive models for nonlinear thermo-electro-mechanical behavior of ferroelectric ceramics.