Effect of Iron Content on the Core Loss and the Stability on for MnZn Ferrite

The effect of the composition of MnZn ferrites on the loss characteristics at 1 MHz and 50 mT has been studied. An increase of the iron content in the system of Fe0.53+xMn0.44-xZn0.03 reduced the core loss. Hysteresis, eddy current, and residual losses were all reduced because of the decrease in Hc, the increase in resistivity, and the upward shift of the resonance frequency at the minimum temperature of core loss, respectively. Magnetizing at 100 mT, however, increased the core loss. Chemical analysis results of Fe2+/Fe and Mn3+/Mn decreased by magnetizing. Moreover, low partial pressure of oxygen during firing, cation defects and the change of the core loss decreased.