Initial permeability studies on high density Cu-Mg-Zn ferrites

We have synthesized Cu-Mg-Zn ferrites by using coprecipitation technique using oxalate precursors. The lattice parameter shows a gradually decreasing trend with increasing Mg2+ content, which is attributed to ionic sizes of Mg2+ and Cu2+ ions. The density of the samples increases with increasing Mg2+ content, which is attributed to smaller ionic size of Mg2+ ions. The Curie temperature does not show appreciable increasing or decreasing trend. The variation in initial permeability (mu(i)) in our compositions is mainly affected by variations of magnetization (M-s) and average particle diameter (D). Also the samples exhibit thermal hysteresis behaviour. The mu(i) decreases with increasing Mg2+ content. This is attributed to a lower value of the anisotropy constant (K-1) for MgFe2O4 than that for CuFe2O4.