A位La和Dy替代Bi_2O_3-ZnO-Nb_2O_5陶瓷结构及介电性能的研究  

Structure and dielectric properties of La-doped and Dy-doped Bi_2O_3-ZnO-Nb_2O_5 based ceramics

作　　者：刘璞凌[1] 丁士华[1] 杨同青[1] 沈波[1] 姚熹[1] 

机构地区：[1]同济大学功能材料研究所,上海200092

出　　处：《上海理工大学学报》2006年第6期531-534,共4页Journal of University of Shanghai For Science and Technology

基　　金：国家973重大基础研究计划资助项目(2002CB613302)

摘　　要：研究了A位La,Dy替代对BZN基陶瓷结构和介电性能的影响.在替代量x≤0.2的范围内,La替代样品均保持单一的立方焦绿石结构;在x<0.15的范围内,Dy替代样品为单一的立方焦绿石相;当x=0.2时,结构中出现杂相.随着La、Dy替代量的增加,陶瓷样品的晶粒尺寸、密度和介电性能发生有规律的变化;低温介电弛豫峰的峰形逐渐宽化;La替代样品的峰值温度向低温方向移动,Dy替代样品的峰值温度向低温方向移动.与x为0.1、0.15和0.2相对应的La替代样品弛豫峰峰值温度tm分别为-95℃,-99℃,-104℃,Dy替代样品弛豫峰峰值温度tm分别为-96℃,-89℃,-85℃.The structure and dielectric properties of La-doped and Dy,doped Bi2O3-ZnO-Nb2O5 ceramics were investigated. The sample exhibits a single cubic pyrochlore phase when La^3 ＋ substitution ≤0.2 and Dy^3＋ substitution 〈 0.15, and the second phase appears when Dy^3＋ substitution = 0.2. The grain size, density values and dielectric properties of BZN samples change regularly with the increasing of doping substitution. The peak temperature of dielectric relaxation moves towards low temperature with the increasing of La^3 ＋ substitution while towards high temperature with the increasing of Dy^3 ＋ substitution. When the substitution content increases from 0.1 to 0.15 and 0.2, the peak temperature of La-doped samples moves from -95℃to -99 ℃ and - 104℃ at 1MHz; the peak temperature of Dy-doped samples moves from - 96 ℃ to - 89℃ and - 85℃ at 1 MHz.

关 键 词：BZN 立方焦绿石 替代 介电弛豫 

分 类 号：TM28[一般工业技术—材料科学与工程]