Synthesis and magnetic properties of ferroxplana type ferrite

The purposes of this study are to investigate the sintering conditions of single Z-type with high electrical resistivity for enhancing the resonance frequency. A mixture of BaCO3, CoO and Fe2O3 powders (final product : Ba3Co2Fe24O41) was calcined at 1273K, sintered at 1473-1623K and then furnace-cooled. The sintering atmospheres used vacuum, Ar, O-2, ail and mixtures of O-2 and Ar. The following properties of sintered samples were examined about bulk density, saturation magnetization, magnetic permeability, dc electrical resistivity and also phase composition. The single phase Z-type ferrite was found in the sample sintered under oxygen at 0.1MPa. The sample sintered at 1573K for 24h under oxygen at 0.1MPa showed a higher resonance frequency over 1.8GHz for having high electrical resistivity and 50% higher value of the real part of permeability than the previously reported results.