Enhanced electric-field-induced strain in 0.7Bi_(1−x)Sm _xFeO₃–0.3BaTiO₃ lead-free ceramics

Piezoelectric actuators play an important role in modern electronic devices. In this work, 0.7Bi_(1−x)Sm_xFeO₃–0.3BaTiO₃ lead-free piezo-ceramics are fabricated through the rapid thermal quenching technique for enhancing the electric-field-induced strain response. All the ceramic samples own a typical perovskite structure, and the morphotropic phase boundary can be achieved after Sm substitution. Additionally, a high T_C of 403 °C and excellent ferroelectricity can be obtained at room temperature for the x = 0.03 composition, together with a large peak-to-peak strain value (∆S = 0.5%). Furthermore, a larger strain value ∆S of 0.45% at 150 °C can also be realized in 0.7Bi_0.95Sm_0.05FeO₃–0.3BaTiO₃ ceramic. Our results could further stimulate the investigations on lead-free ceramics for piezoelectric actuator applications.