Effect of Pre-calcined Method on Dielectric, Ferroelectric, and Piezoelectric Properties of Lead-Free Piezoelectric Li_x(K_(0.5)Na_(0.5))_(1-x)(Nb_(0.8)Ta_(0.2))O_3 Ceramics

摘要

The structure and electrical characteristics of the lead-free Li_x(K_(0.5)Na_(0.5))_(1-x)(Nb_(0.8)Ta_(0.2))O_3 (x=0～0.05) piezoelectric ceramics for the conventional solid-state reaction method and the B-site pre-calcined method were achieved and compared. For the B-site pre-calcined method, the lead-free ceramic material exhibited the excellent electrical and piezoelectric properties. The relative dielectric constant (ε_r) and loss (tan δ) of the Li_x(K_(0.5)Na_(0.5))_(1-x)(Nb_(0.8)Ta_(0.2))O_3for x=0.03 using the B-site pre-calcined method were 1223 and 0.021, respectively. In addition, the electromechanical coupling factors (k_p) and Curie temperature (Tc) was 48.5 % and 315 °C. Finally, the electrical properties of the lead-free Li_x(K_(0.5)Na_(0.5))_(1-x)(Nb_(0.8)Ta_(0.2))O_3 (x=0~0.05) homogeneity ceramics improved by the B-site pre-calcined method were also investigated and discussed.