Effects of sintering temperature on the magnetic properties of Cr substituted Mn-Zn ferrite

Effects of sintering temperature on the magnetic properties of Mn_0.50Zn_0.50Cr_0.4Fe_1.6O₄ have been studied. Ferrite samples were synthesized by combustion method and sintered at various temperatures (1250, 1300 and 1350°C). The structural properties were investigated by X-ray diffraction and indicate that the sample possesses single phase cubic spinel structure. Sintering temperatures (T_s) significantly affect on densification, grain growth and initial permeability of the samples. The average grain size (D), bulk density (ρ_B), real part of the initial permeability (μ´i) increases with increase in sintering temperature whereas coercive field (H_c) decreases. The μ´i strongly depends on average grain size, density and intragranular porosity. The B-H loop of the composition was measured at room temperature. The H_c and hysteresis losses were found to decrease hence softening the material.