Poling dependence and stability of piezoelectric properties of Ba(Zr0.2Ti0.8)O3-(Ba0.7Ca0.3)TiO3 ceramics with huge piezoelectric coefficients

Poling dependence and stability of piezoelectric properties of lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 ceramics were investigated. The experimental results indicated that the poling condition has an obvious effect on the piezoelectric properties due to the existence of a phase transition near room temperature. The best piezoelectric coefficient d33 and planar electromechanical coupling factor kp could reach 630 pC/N and 56%, respectively as the poling conditions were optimized. However, these properties exhibit strong temperature and time dependences, owing to a rather low depolarization temperature (below 80–90 °C) and extremely high aging rate (30% and 25% loss for d33 and kp, respectively, 104 min after poling).

► We prepare BZT-BCT lead-free piezoelectric ceramics with d33 and kp as high as 630 pC/N and 56% respectively.
► Poling condition exhibits an obvious effect on the piezoelectric properties due to the existence of a phase transition near room temperature.
► Strong temperature and time dependences of piezoelectric properties were found owing to a rather low depolarization temperature and extremely high aging rate.