Structural, dielectric and magnetic properties of NiCuZn ferrite grown by citrate precursor method

Fine powders of Ni0.6 − xCuxZn0.4Fe2O4, where 0 ≤ x ≤ 0.4 was prepared by the citrate precursor method. The powders were calcined at 600 °C for a duration of 1 h and sintered at 900 °C for 3 h. The effect of compositional variation on structural, dielectric and magnetic properties of the Cu substituted NiZn ferrite was investigated. X-ray diffraction measurements confirmed the formation of single-phase cubic spinel structure at such low temperature of calcinations and sintering. A maximum density of 4.7 g/cm3 was obtained for the Cu substituted ferrite. The grain sizes were estimated from the SEM micrographs. The addition of copper promoted grain growth, resulting in increase in grain size. Curie temperature, however, was understandably lowered with the increase in Cu content. A saturation magnetization value of 92 emu/g was obtained for the composition x = 0.2. This value is higher than that reported for ferrites prepared by the conventional ceramic method. Ferrite with Cu concentration of x = 0.4, showed the highest value of initial permeability.