An approach to further improve piezoelectric properties of (K0.5Na0.5)NbO3-based lead-free ceramics

Abstract

An approach to further improve piezoelectric properties of (1−x)(K0.5Na0.5)NbO3–xLiNbO3 (KNLN) ceramics, i.e., the optimum poling temperatures (Tp) of KNLN ceramics should be chosen near the polymorphic phase transition temperatures, is proposed. This is contrary to conventional wisdom associated with electrical poling of ceramics. Piezoelectric constant d33 of KNLN (x=0.07) ceramics increases from 210to274pC∕N by selecting optimum Tp. This result indicates that this approach is very effective in improving piezoelectric properties of KNLN ceramics. Moreover, this approach can also be applied to other (K0.5Na0.5)NbO3 based ceramics.