High dielectric constant and good thermal stability from-55 degrees C to 450 degrees C in BaTiO3-based ceramics

摘要

An ultrahigh-temperature X-R type dielectric material, BaTiO3-Na0.5Bi0.5TiO3-Nb2O5-ZnO-Glass with Sm2O3 addition, was successfully prepared. The effects of Sm2O3 content on the phase structure, dielectric and electric properties of ceramics were investigated. Sm ion can substitute for both Ti and Basites, which leads to the decrease of spontaneous polarization and dipolar polarization. As a result, the temperature stability in Er of sample is improved obviously. The 0.2 mol% Sm2O3-doped sample shows the optimal dielectric properties (epsilon(r)=2458; tan delta=1.80%; Delta C/C-20 (degrees C) < +/- 15%, -55 degrees C to 450 degrees C), which satisfies EIA X-R specification. This material with particular focuses on enhancing the upper temperature limit to 450 degrees C, while still maintaining high dielectric constant. (C) 2015 Elsevier B.V. All rights reserved.