Piezoelectric and Dielectric Properties of (Na0.44K0.52)Nb0.84O3-Li0.04(Sb0.06Ta0.1)O3 Ceramics with Sintering Temperature

Lead-free (Na0.44K0.52)Nb0.84O3-Li-0.04(Sb0.06Ta0.1)O-3 (NKN-LST) ceramics were fabricated by the conventional mixed oxide method at various sintering temperatures. The results indicate that the sintering temperature significantly influences the sinterbility, microstructure, phase transition, and electrical properties of the NKN-LST ceramics. For the NKN-LST ceramics sintered at 1060 degrees C to 1100 degrees C, the bulk density increased with increasing sintering temperature and showed a maximum value at a sintering temperature of 1080 degrees C. The Curie temperature of the NKN-LST ceramics slightly decreased with increasing sintering temperature. The dielectric constant, piezoelectric constant, and electromechanical coupling factor increased with increasing sintering temperature, which might be due to the increase in density. However, a high d(33) of 175 rho C/N, k(p) of 39.3%, and epsilon of 4614 were obtained for the NKN-LST ceramics sintered at 1080 degrees C for 4 h.