High-Power Piezoelectric Characteristics at Continuous Driving of Bi4Ti3O12–SrBi4Ti4O15-Based Ferroelectric Ceramics

The high-power piezoelectric characteristics at continuous driving were studied on lead-free piezoelectric ceramics of a mixed bismuth layer-structured ferroelectric, Bi4Ti3O12–SrBi4Ti4O15 (abbreviated as BIT–SBTi) with MnCO3-doping (abbreviated as BIT–SBTi + Mn x wt %). MnCO3-doping to BIT–SBTi can improve its high-power piezoelectric properties such as the mechanical quality factor Q m. The vibration velocity, v 0–p, of the BIT–SBTi + Mn 0.2 wt % ceramics was above 2.0 m/s at 5 V/mm in the case of short- and long-time driving. Also, we observed that the resonance frequency change and temperature on the sample surface at a long-time driving for BIT–SBTi + Mn 0.2 wt % were less than 1.0% and 50 °C at v 0–p of 2.0 m/s, respectively. The high-power characteristics of BIT–SBTi + Mn x wt % were superior to those of hard Pb(Zr,Ti)O3 (abbreviated as PZT) at a vibration velocity v 0–p > 1.0 m/s. Therefore, Mn-doped BIT–SBTi-based ceramics are a promising candidate for lead-free high-power applications requiring frequency stability and long-time driving.