Enhanced piezoelectric properties of (Ba0.3Bi0.7)(Mg0.05Fe0.6Ti0.35)O3 piezoelectric ceramics with high Curie temperature

Abstract

(Ba0.3Bi0.7)(Mg0.05Fe0.6Ti0.35)O3 ceramics were either doped with vanadium or sintered in calcined powder with the same composition. Compared to an undoped ceramic sintered without the calcined powder, both ceramics showed reduced leakage current densities (lower than 1 × 10-7 A/cm2) and absence of dielectric relaxation behaviors observed in frequency- and temperature-dependent dielectric measurements. The Curie temperatures of both samples were higher than 460°C. The maximum field-induced strain over the applied field, Smax/Emax, of 366 pm/V of the undoped ceramic sintered without the calcined powder increased to 455 and 799 pm/V for the V-doped ceramics and the ceramics sintered with the calcined powder, respectively. The increase was related to a reduced concentration of bismuth vacancy–oxygen vacancy defect dipoles.

Keywords

• Piezoelectrics
• domain structure
• lead-free
• high Curie temperature
• dopant