Magnetic properties and related mechanisms of iron-based soft magnetic composites with high thermal stability in situ composite-ferrite coating

摘要

Fe@Composite-Ferrite soft magnetic composites (SMCs) were successfully fabricated by ions doping on the surface of Fe@Fe3O4 powders which can improve the thermal stability and insulation. Compared with the traditional SMCs which were constructed by soft magnetic particle and non-magnetic boundary, this new material maintains high B-m of 1.3214 T at 5000 A/m, 50 Hz, high mu(max) of 625.14 and low P-cm of 10.02 W/kg at 50 Hz, 1.3 T. A three-dimensional simulation loss model and correlation theory of magnetic domain walls were used to analyze the relative loss mechanism and the effect of the new ferrite coating on the domain walls during magnetization. The novel composite-ferrite boundary greatly reduces the pinning, promoting domain wall motion and increasing the number of active magnetic objects. (C) 2020 Elsevier B.V. All rights reserved.