Microstructure and magnetic studies of Mg–Ni–Zn–Cu ferrites

Soft Mg–Ni–Zn–Cu spinel ferrites having general chemical formula NixMg0.5−xCu0.1Zn0.4Fe2O4 (where x = 0.1, 0.2, 0.3, 0.4 and 0.5) were prepared by standard double sintering ceramic method. The samples were characterized by X-ray diffraction at room temperature. The X-ray diffraction (XRD) study revealed that lattice parameter decreases with increase in Ni content, resulting in a reduction in lattice strain. The electrical and magnetic properties of the synthesized ferrites have been investigated as a function of temperature. The variation of initial permeability and AC susceptibility with temperature exhibits normal ferrimagnetic behavior. The variation of initial permeability with frequency is studied. The Curie temperature (TC) in the present work was determined from initial permeability and AC susceptibility. The Curie temperature increases with Ni content.