Study on the Dielectric Properties of 0.75Pb(Mg_1/3Nb_2/3)O_3–0.25PbTiO₃ Ceramic Under Hydrostatic Pressure

Abstract

The dielectric properties of 0.75Pb(Mg_1/3Nb_2/3)O₃-0.25PbTiO₃ (PMN-25PT) ceramic under hydrostatic pressure and pressure-induced phase transition were investigated. PMN-25PT ceramic is pure perovskite with weak relaxation at 1 bar. With increasing hydrostatic pressure, the temperature, T _m, of top dielectric constant decreases, °C/kbar, frequency dispersion and phase transition diffuse increases, remnant polarization decreases continuously. The hydrostatic pressure dependence of dielectric constant () is similar to the temperature dependence of dielectric constant. The relax ferroelectric-paraelectric (RFE-PE) phase transition was induced by hydrostatic pressure and the transition was gradual change process with stronger relaxor behavior than by temperature-induced.

Keywords:

• Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ ceramic
• hydrostatic pressure
• dielectric relaxation
• pressure-induced phase transition

Acknowledgments

This work was ffinancially supported by the National Basic Research Program of China (973 Program) (Grant No. 2009CB623306), the National Natural Science Foundation of China (Grant No.60528008) and the Key Science and Technology Research Project from the Ministry of Education of China (Grant No. 108180).