Microstructure and piezoelectric properties of (Bi0.5Na0.5)1-xBaxTi1-x(Fe0.5Nb0.5)xO3 ceramics

In this paper, we report the synthesis, microstructure and some piezoelectric properties of (Bi0.5Na0.5)(1-x)BaxTi1-x(Fe0.5Nb0.5)(x)O-3 (abbreviated as BNBTFN, x = 0.000, 0.025, 0.050, 0.065, 0.075 and 0.100). The BNBTFN powders were prepared by solid-state reaction method, and their green compacts were sintered at 1150 degrees C for 2 h. XRD study confirmed that there was no second phase for all the compositions. Morphotropic phase boundary (MPB) of rhombohedral and tetragonal phases existed at x similar to 0.050, which was close to that of the BNT-BT system. With increasing x, diffuse phase transition, decrease in transition temperature (T-m), and increase in dielectric maximum at the transition temperature (erm) were observed. The A and B sites simultaneous substitutions, i.e. Ba2+ into (Bi0.5Na0.5)(2+) and (Fe0.5Nb0.5)(4+) into Ti4+, have some positive effects on piezoelectric properties for x <= 0.05 of (Bi0.5Na0.5)(1-x)BaxTi1-x(Fe0.5Nb0.5)(x)O-3, despite the lowering of depolarization temperature. (C) 2016 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University.