Normal sintering of (K_0.5Na_0.5)NbO₃-LiNbO₃ lead-free-piezoceramics and its electrical properties

Lead-free-piezoceramic 0.94[(K_0.5Na_0.5)NbO₃] -0.06LiNbO₃ were prepared by a traditional ceramic processing. The effect of sintering temperature on the density and the electric properties of KNN-LN ceramics were investigated. The results showed that the density of the sintered KNN-LN ceramics changed dramatically in a narrow temperature range of 1020-1100°C. The density of the ceramics sintered at 1070°C reached a maximum value of 4.28 g/cm³(95% of the theoretical density). The ceramic sintered at 1100°C showed a maximum piezoelectric coefficient of about 105 pC/N and a maximum Curie temperature of 431°C, and the coercive field and remanent polarization were 8.56 kV/cm and 11.17 μC/cm² respectively.