Temperature Dependence of Piezoelectric, Dielectric, and Elastic Properties of Lead Lanthanum Zirconate Titanate Ceramics

Abstract

The piezoelectric resonance and the ferroelectric hysteresis loop in 8/65/35 lead lanthanum zirconate titanate (PLZT) ceramics were measured simultaneously at temperatures ranging from 20 to 140°C. The complex elastic compliance and the complex piezoelectric and dielectric constants were extracted from the piezoelectric resonance data, while the temperature-dependent remanent polarization and coercive field were obtained from the ferroelectric hysteresis loops. From the temperature behavior of the above quantities, it is possible to conclude that below 50°C, a strong dc electric field induces a long-range ferroelectric order, while in the temperature range of 90–140°C, the piezoelectric resonance peak and the slim ferroelectric hysteresis loop are both a consequence of short-range polar clusters. In particular, the smeared continuous transition through which the long-range ferroelectric state is established reflects itself in the changes of the electrical and electromechanical quality factor.