Preparation and magnetic properties of MgZn and MnZn ferrites

Synthesis of magnesium-zinc [(Mg0.63Zn0.37)(Mn0.1Fe1.8)O3.85] and manganese-zinc [(Mn0.55Zn0.35Fe0.1)Fe2O4] ferrites by solid-state reaction method is described. Brunauer-Emmett-Teller (BET) surface areas of the ferrite powders used for synthesis were 2.63 m2/g for magnesium-zinc ferrite and 2.86 m2/g for manganese-zinc ferrite respectively. The dense sintered bodies of MgZn and MnZn ferrites obtained at 1250-1300 deg. C were characterized by the presence of Fe2O3 particles uniformly dispersed through a cross-section. Saturation magnetization and hysteresis loops of MgZn and MnZn ferrites were measured using a vibrating magnetometer for both powdered and sintered samples. The samples were distinguished by small core losses and small coercive forces characteristic for soft magnetic materials. The hysteresis loops width for powdered materials were of the order of 15-35 Oe, whereas for sintered specimens they were less than 1 Oe. The saturation magnetization for powders were different from that for sintered samples. The microstructure, chemical, and phase analyses of powders and sintered bodies of ferrites were conducted by scanning electron microscopy (SEM), by energy dispersion X-ray spectroscopy (EDS), and X-ray diffraction (XRD)