Effect of SrTiO 3 modification on dielectric, phase transition and piezoelectric properties of lead‑free Bi 0.5 Na 0.5 TiO 3 ‒CaTiO 3 ‒SrTiO 3 piezoelectric ceramics

摘要: This study investigated the structures, dielectric, ferroelectric and piezoeletric properties of lead-free (0.99‒x) Bi0.5Na0.5TiO3‒0.01CaTiO3‒xSrTiO3 (BNT‒CT‒100xST, x = 0.22–0.30) piezoelectric ceramics. These piezoceramics were successfully prepared using conventional solid-state reaction method sintered at 1175 °C for 2 h. It was found that a phase transition from nonergodic relaxor to ergodic induced by ST modification in BNT‒CT Consequently, large electromechanical strain 0.20% corresponding high normalized $$d_{33}^{*}$$ 667 pm/V obtained even under 3 kV/mm BNT‒CT‒28ST Therefore, it is noted BNT‒CT‒100xST ceramics can be promising candidates actuator applications.