Phase Diagram of Ternary Pb(Mg_1/3Nb_2/3)O₃-PbZrO₃-PbTiO₃ Ferroelectric Ceramics Prepared Via a B-site Oxide Mixing Route

Abstract

xPb(Mg_1/3Nb_2/3)O₃-yPbZrO₃-(1-x-y)PbTiO₃ (PMN-PZ-PT) ferroelectric ceramics were prepared by the conventional ceramic processing via a B-site oxide mixing route. Complete solid solutions can be formed for PMN-PZ-PT in the whole composition range studied, which exhibits pure tetragonal, morphotropic phase boundary (MPB) or rhombohedral perovskite structure depending on compositions. Enhanced structure and electrical performance detected by XRD measurement, and dielectric, ferroelectric and piezoelectric properties characterization confirm the MPB effect. Such phenomena correspond well with the composition-induced successively structural change from rhombohedral, across MPB, and to tetragonal perovskite structure with the increase of the PbTiO₃ content. The preliminary composition phase diagram of the PMN-PZ-PT system is determined by XRD measurement combining with electrical properties characterization. The mechanisms of the structure and electrical properties enhancement are related to easy paths with flattened free energy induced by polarization rotation and polarization extension.

Keywords:

• PMN-PZ-PT ceramics
• B-site oxide mixing route
• MPB
• electrical properties
• phase transition

Funding

The authors thank the National Natural Science Foundation of China (Grant No. 51342002) and the Priority Academic Program Development of Jiangsu Higher Education Institutions for financial support.