High temperature piezoelectric ceramics (1-x)BiScO₃-xPbTiO₃ near the morphotropic phase boundary (MPB)

(1-x)BiScO₃-xPbTiO₃ (BS-PT) ceramics exhibits excellent dielectric and piezoelectric properties in the vicinity of the morphotropic phase boundary (x=64.0% mol fraction PbTiO₃), which separates the rhombohedral phase from tetragonal phase. In our study, the pure perovskite BS-PT ceramics was obtained with compositions near the MPB for x varying from 64.0% to 65.5% using traditional solid state reaction. The perovskite phase formation process and microstructure were investigated and also the dielectric and piezoelectric properties were studied. The results show that BS-PT ceramics with x=64.5% has an optimized piezoelectric characterization, its piezoelectric coefficient d₃₃ can reach to as high as 500 pC/N at room temperature, the Curie temperature (T_c) can reach to 438°C, with the remnant polarization Pr=44 μC/cm², electrical field reduced strain 3.5‰. Our research results show that the BS-PT ceramics with the compositions near the morphotropic phase boundary is a good candidate material for the piezoelectric actuator and transducers.