Abstract
(1-x)Ba0.5Sr0.5TiO3(BST)-xMg2SiO4 (MS) composite ceramics have been synthesized in-situ via a citrate-nitrate combustion process, and their structure and effective dielectric response have been investigated. The compositions with x ≥ 0.3 formed a second phase Ba2TiSi2O8, besides BST and MS phases. The BST-MS composites showed an uniform microstructure with MS particles homogeneously dispersed in BST particles. The temperature at the permittivity maxima of the composites was nearly unchanged with increasing the volume fraction of MS (ƒMS) from 0.1 to 0.4 and then slightly decreased with further increasing ƒMS. According to the modified effective medium approx-imation couple with the spherical inclusion model, the permittivity (ϵBST) of BST in the composites was strongly dependent on ƒMS, which was defined by the relation .
Funding
This research was financially supported by the Natural Science Foundation of China (Grant no. 51202234).