Enhanced piezoelectric strain response in<1100? grain-oriented lead-free bismuth ferrite-based piezoelectric ceramics

The <1100 & rang; grain-oriented 0.11(Bi0.5K0.5)TiO3-0.23BaTiO(3)-0.02Bi(Mg0.5Ti0.5)O-3-0.64BiFeO(3) piezoelectric ceramics were prepared by a reactive templated grain growth method using a platelike H1.08Ti1.73O4 center dot nH(2)O (HTO) template and Bi2O3-KHCO3-MgO-Fe2O3-BaCO3 matrix particles. The high degree of texturing (a Lotgering orientation factor of 80%) and high density (95%) were achieved by employing weight-pressing treatment during the binder-removal and sintering treatment along with optimizing the sintering temperature. The water-quenching treatment has a significant impact on the enhancement of dielectric, ferroelectric, and piezoelectric properties with the increase of dielectric constant, remanent polarization, and piezoelectric strain constant from 764, 13.6 mu C/cm(2), and 384 pm/V for the as-sintered ceramics to 812, 29.9 mu C/cm(2), and 526 pm/V after the water-quenching treatment at 850 & DEG;C, respectively. The obtained piezoelectric strain constant with a 1.8 times enhancement compared to that of the ceramics with randomly oriented grains is significantly higher than those reported for other lead-free piezoelectric ceramics with Curie temperature > 300?. This study suggested the strong potentiality of this material system for high-temperature actuator application.