Effects of the Second Component on the Structure and Electrical Properties of Na_(1/2)K_(1/2)NbO_3-Based Lead-Free Piezoelectric Ceramics

摘要

(Na_(1/2)K_(1/2)NbO_3 (NKN) and 0.95NKN-0.05AB (AB = CaTiO_3 (CT), LiSbO_3 (LS), (Ba_(1/2)Sr_(1/2))TiO_3 (BST)) lead-free piezoelectric ceramics were prepared by conventional solid-state reaction method. XRD measurement confirmed that the second component doped NKN ceramics exhibit pure tetragonal perovskite structure. The addition of the second component greatly increases relative density and improves electrical properties of the NKN ceramics. Especially, the 0.95NKN-0.05LS ceramics exhibit high densifica-tion, being 93.16% of the theoretical density, rather homogenous micromorphology, and excellent integral electrical properties, where the value of dielectric constant maximum epsilon_m at 1kHz is 4780, remanent polarization P_r is 19.66 mu C/cm~2 and piezoelectric constant d_(33) is 194pC/N.