【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。更多还原

【Abstract】 (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)TiO3ceramics 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) TiO3ceramics,and the soluble limitation of Zn2+ and Mg2+(x(Zn),y(Mg)) are 0.10 mol and 0.15 mol,respectively. As the Zn2+ or Mg2+ substitution content exceeds to the soluble limitation,the second phase of Ca2Zn4Ti15O36 or MgTi2O5 is formed. With the increase of Zn2+ or Mg2+ 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 Zn2+ substitution,but the Qf value solely increases with the increase of Mg2+ substitution. The dielectric properties(εr,Qf,τf) of [(Ca0.85Zn0.15)0.61Nd0.26]TiO3 ceramics sintered at 1250 ℃ 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 1250 ℃.更多还原