Phase structure and properties of textured KNN-LTN lead-free piezoelectric ceramics

The textured K_0.48Na_0.52NbO₃-LiTa_0.5 Nb_0.5O₃(KNN-LTN)lead-free ceramics were fabricated by the reactive templated grain growth(RTGG) technique with the plate-like NaNbO₃ particles as template. The effects of soaking time on the phase structure, the texture fraction and the electrical properties were investigated. The results show that the textured ceramics contain perovskite KNN-LTN and tungsten-bronze-type K₃Li₂Nb₅O₁₅ phases. The texture fraction increased with the increasing soaking time and it reached the maximum value of 0.725 at soaking time of 10 h. The dielectric constant increased and the dielectric loss decreased with the increasing soaking time. Compared with the conventional ceramics, the piezoelectric constant d₃₃ of textured ceramics enhanced and increased with the increasing soaking time.