2011/04/27 by Guofeng Yao, Xiaohui Wang, Tieyu Sun +1
Materials Science · Engineering · #Ferroelectric and Piezoelectric Materials #Microwave Dielectric Ceramics Synthesis #Multiferroics and related materials
paper · pdf · doi:10.1111/j.1551-2916.2011.04563.x
Effects of CaZrO 3 on BaTiO 3 –MgO–MnO 2 –Y 2 O 3 nonreducible ceramics were investigated. The specimens modified by CaZrO 3 in the range from 0 to2 mol% were prepared via conventional mixing method. Transmission electron microscopic analysis revealed that doping elements were enriched at grain boundaries and “core–shell” structures were formed. The addition of CaZrO 3 could lower the sintering temperature. The Curie temperature was shifted to a higher point with increasing CaZrO 3 , attributed to the existence of an internal stress produced by lattice mismatch between grain cores and shells. Temperature dependence of dielectric constant and capacitance change were also dependent on CaZrO 3 content. With the increasing of CaZrO 3 content, the insulation resistivity was improved whereas the degradation under direct current electrical field was significant. Therefore, a proper CaZrO 3 content is crucial to obtain high performance X8R nonreducible BaTiO 3 ‐based dielectrics.