Transport and magnetic permeability study of SrCu2−x/2TixFe16−xO27 W-type hexaferrites

A series of polycrystalline W-type hexaferrite with the composition SrCu2−x/2TixFe16−xO27 (with X=0.0, 0.8, 1.2, 1.6 and 2.0) were prepared by using the conventional ceramic method to study their transport and initial magnetic permeability as a function of temperature. The behavior of the DC electrical conductivity σDC with temperature indicates that all samples have a semi-conducting nature. The negative sign of the thermoelectric power coefficient α reveals that all samples are n-type semi-conductors. The results of the charge carrier mobility suggested that the hopping conduction mechanism of electrons from Fe2+ to Fe3+ is dominant in these samples. The behavior of the initial magnetic permeability μi with temperature reveal three distinct regions on the μi (T) curves. The observed behavior in μI (T) curves was attributed to the anomalous behavior of the effective magneto-crystalline anisotropy constant Keff and its component with temperature.