Electrical properties of Na0.5Bi2.5Ta2O9-Sr1-xBi2+yTa2O9 solid solution ceramics

The (1-x)[Na0.5Bi2.5Ta2O9] - x[Sr0.8Bi2.15Ta2O9] (0less than or equal toxless than or equal to1) solid solution ceramics were synthesized using a conventional sintering method. All the ceramic samples consisted of a single phase with an orthorhombic symmetry A2(1)am and showed well-developed polarization-electric field hysteresis loops. The temperature dependence of the dielectric constant revealed that the Curie temperature T-c linearly decreased with ail increase in x from 780degreesC(x=0) to 410degreesC(x=1.0). The maximum electromechanical coupling factor (k(p)=8.6%) and mechanical quality factor (Q(m)=7000) with a radial-extensional mode were obtained for the x=0.75 samples.