A位取代对(Ca_(0.61)Nd_(0.26))TiO_3陶瓷烧结特性和介电性能的影响  

Effect of A-site Substitution on Sintering and Dielectric Properties of (Ca_(0.61)Nd_(0.26))TiO_3 Ceramics

作　　者：张启龙[1] 孙慧萍[1] 杨辉[1] 吴飞[1] 

机构地区：[1]浙江大学材料与化学工程学院,杭州310027

出　　处：《无机化学学报》2009年第1期70-75,共6页Chinese Journal of Inorganic Chemistry

基　　金：浙江省重大科技计划项目(No.2006C11119)资助

摘　　要：采用常规固相反应法,以(Ca0.61Nd0.26)TiO3体系为基体成分,研究了A位取代对(Ca0.61Nd0.26)TiO3陶瓷的烧结特性和介电性能的影响规律。结果表明:Zn,Mg的A位取代,促使(Ca0.61Nd0.26)TiO3陶瓷烧结温度从1350℃降至1250℃。Zn,Mg在一定范围内A位取代(Ca0.61Nd0.26)TiO3中的Ca可形成钙钛矿结构的固溶体,Zn、Mg最大固溶度(x(Zn),y(Mg))分别不超过0.1和0.15mol。当取代量超过固溶度后,分别形成Ca2Zn4Ti15O36和MgTi2O5第二相。随Zn和Mg取代量的增加,陶瓷介电常数(εr)和谐振频率温度系数(τf)减小。陶瓷品质因数(Qf)值随Zn取代量先增后减,而随Mg取代量增加,其Qf值一直增大。Zn,Mg最佳取代分别为x(Zn)=0.15和y(Mg)=0.25,在1250℃烧结2h,[(Ca0.85Zn0.15)0.61Nd0.26]TiO3的介电性能:εr=93.60,Qf=12454GHz,τf=+150.3ppm·℃-1,[(Ca0.75Mg0.25)0.61Nd0.26]TiO3的介电性能:εr=72.48,Qf=14622GHz,τf=+108ppm·℃-1。（Ca0.61Nd0.26）TiO3 ceramics were prepared by conventional solid oxide process method. The effect of A-site substitution on sintering and dielectric properties of（Ca0.61Nd0.26）TiO3 ceramics were investigated. The results show that the A-site substitution of Zn or Mg lowers the densification temperature of（Ca0.61Nd0.26）TiO3 ceramics from 1 350 ℃ to about 1 250 ℃. Perovskite solid structure could be formed by appropriate substitution of Zn or Mg for Ca in（Ca0.61Nd0.26） TiO3 ceramics, and the soluble limitation of Zn^2＋ and Mg^2＋（x（Zn）,y（Mg）） are 0.10 mol and 0.15 mol, respectively. As the Zn^2＋ or Mg^2＋ substitution content exceeds to the soluble limitation, the second phase of Ca2Zn4Ti15O36 or MgTi2O5 is formed. With the increase of Zn^2＋ or Mg^2＋ substitution content, the dielectric constant（εr） and the temperature coefficient of resonant frequency （τf） decrease. The quality factor （Qf） firstly increases and then decreases with the increase of Zn^2＋ substitution, but the Qf value solely increases with the increase of Mg^2＋ substitution. The dielectric properties（εt, Qf, τf） of [（Ca0.85Zn0.15）0.61Nd0.26]TiO3 ceramics sintered at 1 250 ℃ are 93.6, 12 454 GHz, ＋150.3 ppm.℃^-1, respectively. And those are 72.48, 14 622 GHz, ＋108 ppm.℃^-1, respectively, for [（Ca0.75Mg0.25）0.61Nd0.26]TiO3 ceramics sintered at 1 250 ℃.

关 键 词：无机非金属材料 钙钛矿结构 A位掺杂 介电性能 稀土 

分 类 号：O614.335[理学—无机化学] O614.231[理学—化学]