Electrical properties and impedance spectroscopy of crystallographically textured 0.675 [Pb(Mg1/3Nb2/3)O3]-0.325 [PbTiO3] ceramics

Abstract

Crystallographically -textured lead magnesium niobate (PMN)-lead titanate (PT) solid solution in the ratio of 0.675PMN-0.325PT was fabricated by tape-casting method using barium titanate (BaTiO3-BT) templates. Random PMN-PT with the same composition was also produced by tape-casting method for comparison. According to electromechanical and dielectric investigations, textured PMN-PT ceramics produced at 1150 A degrees C for 2 h in oxygen atmosphere with 1 vol% BT were found to display the optimum properties. Dielectric constant, dielectric loss and piezoelectric coefficient of these samples were found to be as 1950, 0.002 and 700 pC/N, respectively. The impedance spectroscopy of the samples was conducted and the results of measurements taken at 300 and 500 A degrees C were compared. A significant decrease in the electrical conductivity was observed with the development of texture in PMN-PT. The slightly depressed semicircles that were obtained from Nyquist diagrams indicated non-Debye-type relaxation with a distribution of relaxation time.