Na_(0.4725)K_(0.4725+x)Li_(0.055)Nb_(1+x)O_3无铅压电陶瓷制备及性能研究

A Study on the Preparation and Properties of Lead-free Na_(0.4725)K_(0.4725+x)Li_(0.055)Nb_(1+x)O_3 Piezoelectric Ceramics

采用传统固相反应制备了Na0.4725K0.4725+xL i0.055Nb1+xO3无铅压电陶瓷,研究了KNbO3对Na0.4725K0.4725+xL i0.055Nb1+xO3材料晶体结构和压电性能的影响.XRD图谱表明,随着KNbO3含量的增加,在0.08<x<0.12处为材料的正交相和四方相共存的准同型相界.组成为Na0.4725K0.5725L i0.055Nb1.1O3的陶瓷具有优异的电学性能,d33达178 pC/N,kp达0.288,rε为642,Qm为41.

Na0.4725K0.4725＋xLi0.055Nb1＋xO3 Lead-free piezoelectric ceramics have been synthesized by the conventional ceramic fabrication technique. The effects of KNbO3 addition on crystal structure and piezoelectric properties were investigated. XRD diffraction patterns reveal that the composition of 0.04 〈 x 〈 0.10 corresponds to morphotropic phase boundary （MPB） between orthorhombic and tetragonal phase. The samples with composition Na0. 4725K0.5715 Li0.055Nb1.1O3 exhibit optimum electrical properties： piezoelectric constant （d33） is 178 pC/ N, electromechanical coupling （kp） is 0. 288, dielectric constant （εr） is 642, mechanical quality factor （Qm） is 41.