Influence of Boron Content in Iron Oxide on Performance of Mn-Zn Ferrites

The ferrites of PC30 (Mn-Zn ferrites) were prepared by using a dry processing route. The effect of Mn-Zn ferrites doped with H3BO3 was investigated on the basis of microstructure analysis. The results of the samples doped with H3BO3 less than 5×10−5 showed that the doping had no significant effect on power loss, initial permeability, fine grain microstructure, and density of Mn-Zn ferrites. With the further increase in H3BO3 doping (up to 1×10−4), the microstructure of Mn-Zn ferrites is in the critical state between fine grain and “sandwich”, and the initial permeability and density of Mn-Zn ferrites begin falling quickly; the increased H3BO3 doping also results in deteriorated power loss properties. Thus, the control of the boron content in iron oxide is of utmost importance for the quality of Mn-Zn ferrites in producing process.