文献类型：期刊文献

中文题名：Nb_2O_5掺杂对SrTiO_3陶瓷显微结构和微波介电损耗的影响

英文题名：Effect of Nb_2O_5 Doping on Microstructures and Microwave Dielectric Loss of SrTiO_3 Ceramics

作者：韩蕊[1];李蔚[1];汪霖[2];严嵩[1]

机构：[1]华东理工大学材料科学与工程学院,上海200237;[2]昆山特乃博先进材料技术有限公司,江苏昆山215321

年份：2017

卷号：43

期号：6

起止页码：800

中文期刊名：华东理工大学学报（自然科学版）

外文期刊名：Journal of East China University of Science and Technology

收录：北大核心:【北大核心2014】；CSCD:【CSCD_E2017_2018】；

语种：中文

中文关键词：钛酸锶;Nb2O5掺杂;显微结构;微波介电损耗

外文关键词：SrTiO3 ; Nb2O5 doping; microstructures; microwave dielectric loss

摘要：采用无压烧结工艺制备了Nb_2O_5掺杂SrTiO_3陶瓷,研究了Nb_2O_5掺杂量对SrTiO_3陶瓷相组成、显微结构和微波介电损耗的影响。结果表明:Nb_2O_5掺杂对SrTiO_3陶瓷的相结构没有产生明显的影响,但会在一定程度上阻碍样品的致密化,同时促进晶粒的生长。随着Nb_2O_5掺杂量的增加,SrTiO_3陶瓷的介电常数从296逐渐下降至230左右,温度系数从1.714×10-3℃-1逐渐下降至1.629×10^(-3)℃-1,Q×f值则先急剧升高,之后又慢慢下降。当Nb_2O_5掺杂量为0.15%(质量分数,下同)时,SrTiO_3陶瓷样品的介电损耗最低,Q×f可达6 281GHz,大约是纯SrTiO_3(1 145GHz)陶瓷样品的5.5倍(此时介电常数约为270,温度系数约为1.684×10^(-3)℃^(-1))。此外,对材料显微结构、介电常数、温度系数特别是介电损耗变化的原因进行了分析。
Nb-doped SrTiO 3 ceramics were prepared via sintering without extra pressure. Effects ofNb2 O5 contents on the phase composition, microstructures and microwave dielectric loss of SrTi0 3 ceramics were investigated. Results showed that Nb20 5 doping has no evident impact on phase composition but hinders the densification and promotes the grain growth of samples to some extent. Upon increasing the amount of Nb2 O5 doping,the permittivity （ εr ） of SrTiO3 ceramics decreased from 296 to 230 and the temperature coefficient reduced from 1. 714×10-3 to 1. 629 × 10-3 ℃-1 gradually, while the Q ×f value increased sharply at f irs t and then decreases slowly. When 0. 15% （mass fraction） Nb2O5 were doped, thedielectric loss of SrTi03 ceramics was the lowest, and the Q×f reached 6 281 GHz （the dielectric constant was about 270 and the temperature coefficient 1. 684× 10-3 ℃ -1） , which is about 5. 5 times as high as that of the un-doped samples （1 145 G H z）. The reasons for the changes of microstructures,dielectric constants, temperature coefficients especially the dielectric loss were also discussed.