中文摘要：

采用传统固相法制备了0.96(KxNa1-xNbO3)-0.04Bi0.5Na0.5ZrO3(0.96KxN1-xN-0.04BNZ,x=0.48,0.49,0.50,0.51,0.52)无铅压电陶瓷，系统研究了K含量对0.96KxN1-xN-0.04BNZ压电陶瓷晶相组成、显微结构及压电性能的影响规律。结果表明：0.96KxN1-xN-0.04BNZ陶瓷均具有纯钙钛矿结构，在x=0.50-0.51时为正交-四方两相共存的准同型相界组成；样品的体积密度随着烧结温度的升高先增大后减小，在1120℃下保温3h体积密度最高，相同烧结温度下，样品的体积密度随K+含量的增加先增大后减小，并在x=0.50时，体积密度达到最大值ρ=4.56g/cm3；陶瓷样品的压电常数d33、机电耦合系数kp、介电常数εr等随着x值的增加呈现出先增大后减小，而陶瓷的介电损耗tanδ和机械品质因数Qm则呈现出相反的趋势。在x=0.50时，陶瓷获得优异的电性能，其d33=305pC/N；kp=36.8%；Qm=49；εr=1390；tanδ=3.2%，居里温度TC=320℃。

英文摘要：

0.96(KxNa1-xNbO3)-0.04Bi0.5Na0.5ZrO3(0.96KxN1-xN-0.04BNZ,x=0.48,0.49,0.50,0.51,0.52)ceramics were prepared by conventionalsolid state reaction method.The crystal structure,micromorphology and electrical properties of0.96KxN1-xN-0.04BNZ piezoceramics weresystemically investigated.The results indicated that all the samples have a pure perovskite structure,and a morphortropic phase boundary(MPB)region with the coexistence of orthorhombic and tetragonal phases can be found in the composition x range of0.5-0.51.The bulkdensity of the sample first increases and then decreases with the firing temperature increasing.The highest density was achieved at1120℃for3h,the bulk density of the sample first increases and then decreases with the content of K increasing,the bulk density reaches themaximum(ρ=4.56g/cm3)at x=0.5.The piezoelectric constant d33,electromechanical coupling factor kp and the dielectric constantεr of thesamples first increases and then decreases with the increasing of x content,while the mechanical quality factor Qm and dielectric loss tanδof the ceramics show opposite trend.The optimized piezoelectric properties can be obtained for the ceramics with x=0.50composition asfollows:d33=305pC/N,kp=36.8%,Qm=49,εr=1390,tanδ=3.2%and Curie temperature TC=320℃.