Field-induced phase transitions in Bismuth-based perovskites: A new approach to lead-free high-strain piezoceramics

The ferroelectric and piezoelectric properties of solid solutions containing various phase fractions of bismuth sodium titanate, barium titanate and potassium sodium niobate are investigated at different temperatures. It is possible to obtain very high strain in these materials near their respective depolarization temperature. The origin of this high strain is the combination of the piezoelectric effect with a field-induced phase transition from a low-field antiferroelectric to a high-field ferroelectric phase.