A MODEL FOR THE STRUCTURAL HYSTERESIS IN POLING AND THERMAL DEPOLING OF PZT CERAMICS

A structural hysteresis associated with domain orientation during poli ng and thermal depoling of lead titanate zirconate (PZT) ceramics has been observed. The poled materials appear to lose their piezoelectric properties at a temperature somewhat below the Curie temperature and y et the domain configurations remain unchanged. The above phenomenon is successfully explained by a model which predicts that upon thermal de polarization, poled ceramics undergo transformation from the poled sta te into the antiferroelectric state before returning back to their ori ginal unpoled state.