High Dielectric Constant and Low-loss Dielectric Ceramics of Sr_5 LnTi_3Ta_7O_(30)(Ln=La,Nd,Sm and Y)  

作　　者：TU Wenmao CHEN Pu PENG Xiyang LIU Ting 

机构地区：[1]School of Resource and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2008年第2期218-221,共4页武汉理工大学学报（材料科学英文版）

摘　　要：Polycrystalline Sr5LnTi3Ta7O30 （Ln=La, Nd, Sm and Y） ceramics were prepared as single-phase materials through conventional solid-state ceramics method. The structure was characterized by X-ray diffraction method and scanning electron microscopy （SEM）. The dielectric properties were measured from room temperature to 400℃. All compounds are paraelectric phases adopting the filled tetragonal tungsten bronze （TB） structure at room temperature. At 1 MHz their dielectric constant （ετ） varied from 109 to 139, dielectric loss changed from 0.003 3 to 0.005 8, and the temperature coefficients of the dielectric constant （τε） moved from -710 to -880×10^-6℃^-1.Polycrystalline Sr5LnTi3Ta7O30 （Ln=La, Nd, Sm and Y） ceramics were prepared as single-phase materials through conventional solid-state ceramics method. The structure was characterized by X-ray diffraction method and scanning electron microscopy （SEM）. The dielectric properties were measured from room temperature to 400℃. All compounds are paraelectric phases adopting the filled tetragonal tungsten bronze （TB） structure at room temperature. At 1 MHz their dielectric constant （ετ） varied from 109 to 139, dielectric loss changed from 0.003 3 to 0.005 8, and the temperature coefficients of the dielectric constant （τε） moved from -710 to -880×10^-6℃^-1.

关 键 词：dielectric properties PARAELECTRIC tungsten bronze TANTALATES 

分 类 号：TQ174.75[化学工程—陶瓷工业]