Effect of sintering temperature on the piezoelectric properties in BiFeO3-BaTiO3 ceramics

Abstract

The effect of the sintering temperature was investigated in 0.75BiFeO3-0.25BaTiO3 lead-free piezoelectric ceramics. Undoped 0.75BiFeO3-0.25BaTiO3 ceramics were prepared by using a conventional ceramic process. When the sintering temperature was increased from 940 °C to 1,020 °C, the bulk density and the dielectric constant increased at first, reached their maximum values at 980 °C, and then decreased. The grain size increased greatly when the sintering temperature was increased from 960 °C to 980 °C and then was saturated with a further increase in the sintering temperature. The piezoelectric constant d33 and the electromechanical coupling factor k p displayed their highest values at sintering temperatures of 980 °C to 1,000 °C. The relationship between the piezoelectric properties and the microstructure is discussed.