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

In this study, lead-free (LiNaK)(NbTaSb)O 3 piezoelectric ceramics were fabricated on the basis of the amount of K 2 CO 3 addition, and their piezoelectric and dielectric properties were investigated by varying the amount of K 2 CO 3 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 % K 2 CO 3 -added (Li 0.04 Na 0.44 K 0.52 ) (Nb 0.86 Ta 0.1 Sb 0.04 )O 3 ceramics exhibit excellent piezoelectric properties in an experiment performed on the basis of the amount of K 2 CO 3 addition. That is, a 0.1 wt % K 2 CO 3 -added specimen showed a large electromechanical coupling factor k p =0.494, a large piezoelectric constant d 33 =274 pC/N, and a high density of 4.65 g/cm 3 at the poling temperature of 20 °C.