Magnetic properties of Fe-based soft magnetic composite with insulation coating by resin bonded Ni-Zn ferrite nanofibres

摘要

Soft magnetic composite material consisting of iron powder insulated by Ni-Zn ferrite nanofibres was prepared, where the nanofibres were bonded by the resin in various amounts in order to find the ratio for optimal insulation coating. The structure of material was documented and the magnetic and electrical properties were analysed. The optimal ratio of ferrite nanofibres to resin was found to be 1/2:1/2, as this sample exhibited the highest total and differential permeability, the lowest hysteresis and total energy losses and the highest number of active magnetic objects, found from the excess loss analysis, which revealed the highest proportion of domain wall displacements within the magnetization process. The magnetic properties values were reached better than for previous iron-resin composites. The relatively high real part of complex permeability was obtained together with its relatively high frequency stability. The optimal coating from ferrite nanofibres probably improved magnetic interaction between ferromagnetic particles by means of lowering inner demagnetizing fields.