Effect of Copper Substitution on the Dielectric and Magnetic Properties of Low-Temperature-Sintered Z-type Ferrites

Abstract

Cu-substituted Z-type ferrite (Ba3Co2-xCuxFe24O41, where X=0, 0.2, 0.4, 0.6 and 0.8) powders were synthesized using a citrate precursor method. Single Z-type phases were found by X-ray diffraction to form at a relatively low temperature of 1100–1150°C. With an appropriate sintering aid, highly dense Cu-substituted ceramics could be obtained after sintering below 900°C and these exhibited excellent electromagnetic properties such as high initial permeability up to 7.0 with high cutoff frequencies above 1.2 GHz. The Cu content in the composition has a significant influence not only on the magnetic properties but also on the dielectric properties of the sintered ceramics. In this paper, the effects of copper substitution on the microstructures and properties of the low-temperature-sintered Ba3Co2-xCuxFe24O41 are investigated and discussed. The dielectric constant increases with increasing Cu content, which is explained by the presence of two types of charge carriers.