Effects of particle size and content of silicon resin on the soft magnetic properties of Fe-based magnetic powder cores

Fe-based magnetic powder cores by coating different size of pure iron particles with different content of silicon resin have been fabricated via powder compacting molding process. The Effects of particle size and content of silicon resin on density, DC and AC magnetic properties of magnetic powder cores were studied systematically. The best particle size and content of silicon resin were searched in order to prepare high-performance magnetic powder cores with high density, low loss and high magnetic induction. The investigation showed that, for coating the same particle size of the iron particles, the eddy loss of magnetic powder cores decreased with increasing the coating content of silicon resin. The density of the magnetic cores was also lower with the increasing content of silicon resin, which resulted in the decrease of saturation magnetic induction. With the same content of silicon resin, both the density and the eddy loss of magnetic powder cores increased accompanied by the increased particle size of pure iron particles. While the magnetic hysteresis loss decreased with increasing the particle size. The results revealed that high-performance magnetic powder cores with high density and good soft magnetic properties could be synthesized when coating the pure iron particles of the size for 120 μm with the silicon resin content of 0.5wt%. High magnetization B_{4k(H=4000 A/m)} of 0.96 T and low loss P_{s(B=1 T, f=400 Hz)} of 69 W/kg were obtained for Fe-based magnetic powder cores in this work.