Small-signal piezoelectric properties on Mn-doped BiFeO3–BaTiO3 lead-free piezoelectric ceramics

Abstract

Small-signal piezoelectric characteristics in pseudo-cubic BiFeO3–BaTiO3-based ceramics are rarely studied. In this study, the xMnO2-doped 0.67BiFeO3–0.33BaTiO3 (BF33BT–xMn, x = 0.0, 0.2, 0.4, and 0.6 wt %) ceramics are investigated. Small and large amounts of Mn ions play different roles in resistivity, with the highest resistivity observed at a MnO2 content of 0.2 wt %. The examination of poling conditions revealed the impact of electric field strength and poling time on impedance phase ª. The piezoelectric constant (d33) and electromechanical coupling factor (k33) increase with impedance phase ª, while the mechanical quality factor (Qm) value remains unchanged. Our finding indicates that poled BF33BT–0.2Mn ceramic reaches an impedance phase ª of 73°, k33 of 0.45, Qm of 41.0, and d33 © Qm value of 3856 pC/N. This study contributes to further research on the high-power piezoelectric characteristics of lead-free BiFeO3–BaTiO3-based ceramics.