Ca^2+ doping effects in(K,Na,Li)(Nb0.8Ta0.2)O3 lead-free piezoelectric ceramics  

作　　者：Lei TANG Tengfei LIU Jinxu MA Xiaowen ZHANG Linan AN Kepi CHEN 

机构地区：[1]School of Energy,Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China [2]State Key Laboratory of New Ceramics and Fine Processing,School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China [3]Department of Materials Science and Engineering,Advanced Materials Processing and Analysis Center,University of Central Florida,Orlando,FL 32816,USA

出　　处：《Frontiers of Materials Science》2019年第4期431-438,共8页材料学前沿（英文版）

摘　　要：Lead-free(K0.5-x/2Na0.5-x/2Lix)(Nb0.8Ta0.2)O3(KNLNT)and(K0.49-x/2Na0.49-x/2-LixCa0.01)(Nb0.8Ta0.2)O3(KNLNT-Ca)ceramics were prepared by a conventional ceramic processing.Structural analysis shows that the Ca^2+ doping takes the A site of ABO3 perovskite and decreases the phase transition temperature.Property measurements reveal that as a donor dopant,the Ca^2+ doping results in higher room-temperature dielectric constant,lower dielectric loss,and lower mechanical quality factor.In addition,the Ca^2+ doping does not change the positive piezoelectric coefficient d33,but increases the converse piezoelectric coefficient d 33*significantly.This is likely due to the increase in the relaxation,as well as the appearance of(CaNa/K·-VNa/K’)defect dipoles.

关 键 词：lead-free piezoelectric KNN converse piezoelectric coefficient donor dopant piezoelectric property polymorphic phase transition 

分 类 号：TQ1[化学工程]