（Na0.8K0.2）0.5Bi0.5TiO3-xSrTiO3-0．3％Mn无铅压电陶瓷的结构与性能

采用固相法制备了（Na1-xKx0.5）Bi0.5YiO3-xSrTiO3-0.3Mn系无铅压电陶瓷，研究了该系统的微观结构和压电性能。XRD分析表明所得陶瓷样品在室温下均为三方、四方共存的钙钛矿结构，随着Sr的增加，三方相减少，四方相增加。SEM图谱显示各样品颗粒均匀、具有规则的外形、晶界明显，并且少量Sr的加入使样品更加致密化。该体系样品具有优异的压电性能，在Sr含量为0．02时，压电常数如、平面机电耦合系数k，和厚度机电耦合系数kt同时达到最大值，分别为171pC·N^-1、33．1％和30．5％，Sr具有“软性”添加物的作用

Structure and Properties of (Na_(0.8)K_(0.2))_(0.5)Bi_(0.5)TiO_3 Lead-Free Ceramics Substituted with SrTiO_3

(Na1-xKx)0.5Bi0.5TiO3-xSrTiO3-0.3%Mn lead-free ceramics were prepared by solid-state reaction. The structure and electric properties were studied. XRD results show that all ceramic samples are perovskite with rhombohedral and tetragonal at room temperature. With the increase of Sr content, the phase of tetragonal will increase and the rhombohedral phase will decrease. SEM images show that the grains have regular shape and the crystalline boundaries are obviously observed. The ceramic samples have outstandin...