Magnetic Properties of Cu–Zn Ferrites Doped with Rare Earth Oxides

Abstract

Samples of Cu–Zn ferrites doped with different rare earth ions (La, Sm, Nd, Gd, and Dy) are investigated. X-ray diffraction patterns indicated the presence of a single spinel phase. The lattice parameter is found to be nearly independent of the doped rare earth ion type. The density is measured and the porosity is calculated for each sample. The magnetization is measured on toroidal samples using the induction method. The initial permeability μi is measured as a function of temperature at a constant frequency of 10 kHz and the Curie temperature TC is determined. The variations of magnetization, relative permeability and the initial permeability as a function of the effective magnetic moment of the doped rare earth ion are discussed.