Influence of sintering temperatures on the properties of lithium sodium potassium niobate piezoelectric ceramics

Lithium sodium potassium niobate (Li, Na, K)NbO3 (LNKN) piezoelectric ceramics were prepared by using conventional solid state process. The phase structures of LNKN ceramics were characterized by x-ray diffraction (XRD). ne dielectric properties of LNKN ceramics have been also studied at different temperature and frequency. It was found that LNKN ceramics have high Curie temperature T-c(about 460 degrees C), and relatively high piezoelectric constant d(33) (similar to 200pC/N) and high electromechanical coupling coefficient k(p) (similar to 0.40). Both of the piezoelectric constant d33 and electromechanical coupling coefficient k(p) of LNKN ceramics decreased with the increasing of sintering temperature. The piezoelectric property dependence of composition of LNKN ceramics has also been studied.