A novel temperature stable and high Q microwave dielectric ceramic in Li-3(Mg1-xMnx)(2)NbO6 system

作者:Zhang, Ping*; Liu, Lu; Xiao, Mi; Zhao, Yonggui
来源:Journal of Materials Science: Materials in Electronics , 2017, 28(16): 12220-12225.
DOI:10.1007/s10854-017-7037-9

摘要

The compositions of Li-3(Mg1-xMnx)(2)NbO6 ceramics were prepared by the conventional solid state reaction method. The effects of Mn2+ substitution on the microstructure, sintering behavior and microwave dielectric properties of Li-3(Mg1-xMnx)(2)NbO6 ceramics were investigated systematically. The XRD patterns revealed that all the specimens sintered at 1075-1200 A degrees C remained a single phase with orthorhombic structure. The obtained microwave dielectric properties indicated that appropriate amount of Mn2+ substitution for Mg2+ could significantly promote the grain growth and densify Li3Mg2NbO6 ceramics. The permittivity and Q x f values were strongly dependent on the bulk density and grain size, respectively. And near zero tau (f) values could be realized in the Li-3(Mg1-xMnx)(2)NbO6 (0.02 ae broken vertical bar aEuroex ae broken vertical bar aEuroe0.08) compounds sintered at 1125 A degrees C. To sum up, the x = 0.02 sample sintered at 1125 A degrees C for 4 h exhibited excellent microwave dielectric properties of epsilon(r) similar to 15.22, Q x f similar to 110,582 GHz, tau (f) similar to-4.57 ppm/A degrees C which demonstrated that the Li-3(Mg0.98Mn0.02)(2)NbO6 ceramic would be a novel temperature stable and high Q material for microwave device.