摘要
采用固相反应法研究了Zr^(4+)B位取代Ti^(4+)对Ba_(6-3x)La_(8+2x)Ti_(18)O_(54)(x=2/3)陶瓷结构和介电性能等的影响。结果表明:Zr^(4+)B位取代可使Ba_(6-3x)La_(8+2x)Ti_(18)O_(54)(x=2/3)陶瓷的烧结温度从1 350℃升高到1 600℃;在一定范围内Zr^(4+)取代Ti^(4+)可形成单相类钙钛矿钨青铜型固溶体,Zr^(4+)最大固溶度不超过0.2,超过这一范围,Ba_2ZrO_4会作为第二相出现在固溶体中;少量Zr^(4+)取代Ti^(4+)使Ba_(6-3x)La_(8+2x)(Ti_(1-z)Zr_z)_(18)O_(54)(x=2/3)陶瓷的品质因数大幅度提高,谐振频率温度系数得到改善,但介电常数下降;当Zr^(4+)掺杂量z=0.05时,1 400℃保温2 h烧结后陶瓷获得较佳的微波介电性能,ε_r=86.83,Q_f=5 875 GHz,τ_f=81.99×10^(-6)/℃。
The effect of B site substitution of Zr^（4＋） for Ti^（4＋） on microstructure and dielectric properties of Ba_（6-3x）La_（8＋2x）Ti_（18）O_（54）（x=2/3） ceramics was investigated by solid-state reaction method.The results show that Zr^（4＋） B site substitution for Ti^（4＋） increased the sintering temperature of Ba_（6-3x）La_（8＋2x）Ti_（18）O_（54）（x=2/3） ceramics from 1 350℃to 1 600℃.A single-phase solid solution with like-perovskite tungsten bronze type structure was formed as the Zr^（4＋） substitution for Ti^（4＋） within a certain range,and the maximum solubility of Zr^（4＋） was no more than 0.20.As the Zr^（4＋） solubility exceeded 0.2,a second phase of Ba_2ZrO_4 was detected.With small Zr^（4＋） substitution for Ti^（4＋） in Ba_（6-3x）La_（8＋2x）（Ti_（1-z）Zr_z）_（18）O_（54）（x= 2/3） ceramics,a significant improvement of Q_f value was achieved,the temperature coefficient of resonant frequency（τ_f） was slightly improved and the dielectric constant decreased.When intermingled quantity of Zr^（4＋） was 0.05,the optimal microwave dielectric characteristics of the ceramicsε_r=86.83, Q_f=5 875 GHz andτ_f=81.99×10^（-6）/℃,were achieved after sintering at 1 400℃for 2 h.
出处
《机械工程材料》
CAS
CSCD
北大核心
2010年第5期36-39,71,共5页
Materials For Mechanical Engineering
基金
国防科工委军品配套项目
关键词
介电性能
微波介质陶瓷
类钙钛矿钨青铜结构
dielectric property
microwave dielectric ceramic
like-perovskite tungsten bronze type structure
