Synthesis and microwave dielectric properties of pseudobrookite-type structure Mgb>5 b>Nbb>4 b>Ob>15 b> ceramics by aqueous sol-gel technique
- 作者：H.T. Wu ; mse_wuht@ujn.edu.cn ; W.B. Wu ; Y.L. Yue ; Y.M. Chen ; F. Yang
- 关键词：A. Sol&ndash ; gel processes ; Mg5Nb4O15 ; Nanopowder synthesis ; Microwave dielectric properties
- 刊名：Ceramics International
- 出版年：2012
- 期刊代码：13_02728842
- 类别：ms
- 出版时间：July, 2012
- 卷：38
- 期：5
- 页码：4271-4276
- 文件大小：1027 K
摘要
Pseudobrookite-type Mgb>5 b>Nbb>4 b>Ob>15 b> ceramics were prepared by aqueous sol-gel process and microwave dielectric properties were investigated. Highly reactive nanosized Mgb>5 b>Nbb>4 b>Ob>15 b> powders were successfully synthesized at 600 掳C in oxygen atmosphere with particle sizes of 20-40 nm firstly and then phase evolution was detected by DTA-TG and XRD. Sintering characteristics and microwave dielectric properties of Mgb>5 b>Nbb>4 b>Ob>15 b> ceramics were studied at different temperatures ranging from 1200 掳C to 1400 掳C. With the increase of sintering temperature, density, m>蓻 m>b>m>r m> b> and m>Q m>路m>f m> values increased, and then saturated at 1300 掳C. Excellent microwave properties of m>蓻 m>b>m>r m> b> 鈭?1.3, m>Q m>路m>f m> 鈭?3,300 GHz and m>蟿 m>b>m>f m> b> 鈭尖垝58 ppm/掳C, were obtained finally. The sintering temperature of Mgb>5 b>Nbb>4 b>Ob>15 b> ceramics was significantly reduced by aqueous sol-gel process compared to conventional solid-state methods.