Study of Lead-free Ceramics of the [(K0.5Na0.5) 0.94Li 0.06] 0.97La0.01(Nb0.9Ta0.1)O3 Piezoelectric Composite

Abstract

[(K_0.5Na_0.5)_0.94Li_0.06]_0.97La_0.01(Nb_0.9Ta_0.1)O₃ lead-free ceramics have been prepared by the traditional ceramic method. The calcined powders were encapsulated and sintered in their own atmosphere. Our results reveal that Li⁺, La³⁺ and Ta⁵⁺ diffuse into the (K_0.5Na_0.5)NbO₃ lattice to form a solid solution with a perovskite structure. X-ray diffraction analysis showed a mixture of phases with a predominant orthorombic structure. The dielectric properties plotted vs temperature show a normal phase transition at 399^oC. The piezoelectric behavior is characterized by the values of k_p= 0.34, Q_m=137 and ε_max=1906, allowing us to conclude that a substitute for PZT ceramics is within reach.