Electromechanical Properties of Relaxor Ferroelectric Lead Magnesium Niobate-Lead Titanate Ceramics

Abstract

In this paper, the results of a recent investigation of the dependence of the induced piezoelectric activity on temperature, electric bias field, and frequency and the electrostrictive response in the relaxor ferroelectric lead magnesium niobate-lead titanate ceramics ( (1- x)(Pb(Mg1/3Nb2/3)O3)- x(PbTiO3)) at compositions below 30% PT are presented. It was observed that the electrostrictive strain at temperatures near the dielectric constant maximum T max increases monotonically with increased PT content. For PMN:PT at compositions near 30% PT, the electrostrictive strain under a 10 kV/cm electric field can reach about 0.15% with very little hysteresis. An exceptionally large piezoelectric response with an effective piezoelectric d 33 coefficient in the electric field induced state of over 1,800 pC/N could be achieved for selected PMN:PT compositions and electric bias fields.

Investigation of the electrocaloric effect in a PbMg2/3Nb1/3O3-PbTiO3 relaxor thin film

“…The values of T m and T d in the present work corroborate the observation found for 0.93PMN-0.07PT ceramics. 9 This thermal hysteresis has not been previously observed in relaxor thin films.…”

“…This observation agrees with the proposed phase diagram for 0.93PMN-0.07PT solid solutions. 9 At 18°C, the permittivity displays a reproducible anomaly in the ZFH data that is not readily apparent in the ZFC data ͑the loss data is not smooth enough to read in this way͒. This suggests that no structural phase transition takes place on cooling, which in turn suggests no structural transition on heating, despite observations to the contrary.…”

“…T m and T d are in good agreement with the previously reported phase diagram. 9 Using the indirect method to process the data, the ECE of the film cannot formally be determined in the absence of thermal equilibrium, but large effects of ⌬T = 9°C near room temperature may be possible. 07PT thin film, as a function of starting temperature, due to selected ⌬E ͑E 1 =0͒.…”

Neutron diffraction study of electrostrictive coefficients of prototype cubic phase of relaxor ferroelectric PbMg1/3 Nb2/3 O3

“…1 These materials have been found to be very attractive for such applications as they exhibit large strain S under applied electric field E with almost no electromechanical hysteresis, 1 and the sensitivity of strain response, ‫ץ‬S/‫ץ‬E, can be tuned by the electric field. 2 In this context, many studies have been devoted to the characterization of the electrostrictive coefficients Q kli j of these materials, which are defined by 3 S i j ϭQ kli j •P k •P l , ͑1͒…”

Phase composition of 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 film deposited by radio frequency magnetron sputtering

“…The properties of giant piezoelectric, electrostriction, and diffusion peak in its dielectric versus temperature characteristic have been extensively studied based on the application of actuators, transducers, and capacitors (Levoska et al, 2000). PbMg 1/3 Nb 2/3 O 3 -PbTiO 3 (PMN-PT) exhibits excellent relaxor properties and has likewise been extensively studied (Zhao et al, 1995;Zhang and Zhao, 1997). In bulk material, PMN-PT with compositions having less than 33 mol% of PT show relaxor behavior, associated with a diffuse peak in its dielectric versus temperature characteristic.…”