Effect of Cu and Li substitution on the piezoelectric properties of potassium sodium niobate lead-free ceramics

Abstract

Recently, (K, Na) NbO3 (KNN) ceramics and, based on KNN, (K,Na,Li) NbO3 ceramics, (K,Na,Li)(Nb,Ta,Sb)O3 (LF4) perovskite ceramics were reported to show excellent piezoelectric properties and has been regarded as candidates of lead-free piezoelectric materials. In this study, the effect of CuO addition to Li-modified KNN were investigated. The CuO-doping changed it to hard piezoelectric ceramics but the Qm can be improved to above 400 for Li-modified KNN with a high piezoelectric constant d33 of 100 pC/N.