Effect of Mg Content on Phase Structure and Electrical Properties of (Ba0.97Ca0.03)(Ti0.96-xZr0.04Mgx)O3 Ceramics

Abstract

The Mg-doped (Ba0.97Ca0.03)(Ti0.96-xZr0.04Mgx)O3 piezoelectric ceramics were prepared by conventional sintering technique. Influences of MgO doping content on the phase structure and dielectric, piezoelectric, and ferroelectric properties were investigated. The XRD patterns suggested that a morphotropic phase boundary (MPB) crossing pseudocubic and tetragonal symmetries occurs at the compositions containing 0.5~0.7 at.% Mg. Because of such transitional behavior, the piezoelectric coefficient (d33), electromechanical coupling coefficient (kp), and remanent polarization (Pr) were enhanced to peak values, 327 pC/N, 37.2%, and 15.79 μC/cm2, respectively. However, the dielectric constant (εr) showed a decreasing tendency with raising Mg content.