Piezoelectric and Dielectric Properties of (LiNaK)(NbTaSb)O3 Ceramics with Variation in Poling Temperature

In this study, lead-free (LiNaK)(NbTaSb)O3 piezoelectric ceramics were fabricated on the basis of the amount of K2CO3 addition, and their piezoelectric and dielectric properties were investigated by varying the amount of K2CO3 addition and poling temperature. First, to achieve optimum poling conditions for manufactured specimens, the poling temperature was varied to be 0, 20, 50, 80, and 110 °C. The optimum poling temperature was 20 °C. It was found that 0.1 wt % K2CO3-added (Li0.04Na0.44K0.52) (Nb0.86Ta0.1Sb0.04)O3 ceramics exhibit excellent piezoelectric properties in an experiment performed on the basis of the amount of K2CO3 addition. That is, a 0.1 wt % K2CO3-added specimen showed a large electromechanical coupling factor kp=0.494, a large piezoelectric constant d33=274 pC/N, and a high density of 4.65 g/cm3 at the poling temperature of 20 °C.