Full characterization for material constants of a promising KNN based lead free piezoelectric ceramic
Abstract Potassium sodium niobate (K1 xNaxNbO3, referred to as KNN) solid solutions, which are an important type of lead free piezoelectric materials possessing environmentally friendly features, good piezoelectric response and high Curie temperature, have attracted considerable attention in replacing lead based ceramics. In order to promote the application of KNN based ceramics in piezoelectric devices, we characterized a complete set of material constants of a high performance KNN based ceramic, that is 0.965(K0.48Na0.52) (Nb0.96Sb0.04)O3 0.035Bi0.5Na0.5Zr0.15Hf0.75O3 (KNNS BNZH) whose Curie temperature is 235 degC, piezoelectric coefficient d33 is 380 pC/N and electromechanical coupling factor k33 is 70% These results will benefit the design of piezoelectric transducers and actuators using lead free piezoelectric ceramics.