LAUSR

Lead-free (1−x)K0.5Na0.5NbO3-x mol%Sr2MnSbO6 (abbreviated as KNN–xSMS, x = 0, 1 and 2) piezoelectric ceramics were prepared using the conventional solid-state sintering method. The effects of SMS on the microstructure and electrical properties of the KNN ceramics are investigated. 1 mol% SMS can greatly enhance the densification and increase the piezoelectric properties. Higher doping amounts will decrease the grain size and reduce electrical properties. The x = 0 and 1 samples show normal ferroelectric phase transition behavior, while the x = 2 sample exhibits diffuse phase transition behavior. Besides, after doping 1 mol% SMS, the field-induced unipolar strain and the remnant polarization vary less than undoped KNN ceramics in the temperature range of 30–160 °C. Therefore, doping SMS is an effective way to promote the temperature stability and electrical properties of KNN piezoelectric materials.