摘要
采用溶胶–凝胶法制备Li+取代(K0.5Na0.5)+及Ta5+取代Nb5+的(K0.5Na0.5)NbO3陶瓷粉体,采用无压烧结工艺制备(Na0.50+xK0.50–2xLix)Nb0.9Ta0.1O3(x=0,0.02,0.04)陶瓷样品。研究了前驱体煅烧温度对陶瓷粉体物相组成的影响。分析了不同Li+掺杂量对样品物相组成、微观结构、体积密度及电学性能的影响。结果表明:前驱体的最佳煅烧温度为600℃,通过透射电子显微镜分析陶瓷粉体的粒径为49 nm;不同Li+掺杂量制备的(Na0.50+xK0.50–2xLix)Nb0.9Ta0.1O3陶瓷样品均为正交相钙钛矿结构;随着Li+掺杂量的增加,(Na0.50+xK0.50–2xLix)Nb0.9Ta0.1O3陶瓷的体积密度先增大后减小,介电常数逐渐升高,压电常数先降低再升高,剩余极化强度逐渐升高。Li+掺杂量x为0.04时样品的压电常数(d33=94 pC/N)、相对介电常数(εr=684.33)及剩余极化强度(Pr=98.27μC/cm2)较好。
The ceramic powders,in which Li+ substituted(K0.5Na0.5)+ and Ta5+ substituted Nb5+,were prepared by a sol–gel method,and the(Na0.50+xK0.50–2xLix)Nb0.9Ta0.1O3(x = 0,0.02,0.04) ceramics were prepared via a pressureless sintering method.The effect of calcining temperature on the phase composition of ceramic powders was investigated.The influence of the Li+ substitution on the phase composition,microstructure,density and electrical properties of the ceramics was systematically analyzed.The results show that the optimal calcining temperature is 600 ℃.The analysis by transmission electron microscope indicated that the average size of the ceramic powders was 49 nm.The(Na0.50+xK0.50–2xLix)Nb0.9Ta0.1O3 ceramics had a single-phase perovskite structure with the or-thorhombic symmetry.The density of the(Na0.50+xK0.50–2xLix)Nb0.9Ta0.1O3 ceramics firstly increased and then decreased with the increase of Li+ content,while piezoelectric constant had the opposite transformation.The dielectric constant and remnant polarization were both improved when Li+ content was increased.When Li+ content was 0.04,the samples had an excellent piezoelectric constant(d33 = 94 pC/N),relative dielectric constant(εr = 684.33) and remnant polarization(Pr = 98.27 μC/cm2).
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2012年第3期351-356,共6页
Journal of The Chinese Ceramic Society
基金
北京科技新星计划(2007A080)资助项目
关键词
无铅压电陶瓷
溶胶–凝胶法
钙钛矿结构
微观结构
电学性能
lead-free piezoelectric ceramics
sol-gel method
perovskite structure
microstructure
electrical property
