KNN-BT-BZ系无铅压电陶瓷的研究

Study on KNN-BT-BZ System Lead-Free Piezoelectric Ceramics

采用传统电子陶瓷方法制备了(0.94-x)K0.49Na0.51NbO3-xBaTiO3-0.06BaZrO3(x=0～0.04mol,简称KNN-BT-BZ)体系无铅压电陶瓷,研究BaTiO3含量对该体系陶瓷的晶体结构与压电、介电性能的影响。结果表明:所研究组成范围内所有陶瓷样品均具有单一钙钛矿结构,随着BaTiO3含量x的增加,陶瓷的压电常数d33、平面机电耦合系数kp先增加后降低,机械品质因数Qm和介电常数εT33/ε0均增大,同时介电损耗tanδ减小。当x=0.03时,该组成陶瓷具有较好的压电性能:d33达322pC/N,kp为42%,Qm=193,εT33/ε0=423和tanδ=0.045。

The lead-free piezoelectric ceramics (0.94-x)KNN-xBaTiO3-0.06BaZrO3 (abbreviated as KNN-BT-BZ) with x = 0 ～ 0.04 mol were prepared by conventional solid state reaction method. The effect of BaTiO 3 content on the crystal structure, dielectric and piezoelectric properties was investigated. The results indicate that all samples have a single perovskite structure. With the increasing of BaTiO 3 content, the piezoelectric constant d 33 and the planar electromechanical coupling factor k p increase first and then decrease, the mechanical quality factor Qm and dielectric constant εT33 /ε 0 increase, the dielectric loss tanδ decreases. When x = 0.03, the ceramic exhibits excellent electrical performances as follows: d33 =322 pC/N, k p =42%, Qm =193, εT 33 /ε0 =423 and tanδ =0.045.