Magnetic properties of soft magnetic composites fabricated by injection molding of bimodal amorphous Fe73Si11B11C3Cr2 and crystalline Fe50Co50 powders

Hybrid soft magnetic composites are fabricated using bimodal amorphous Fe73Si11B11C3Cr2 and crystalline Fe50Co50 powders via MIM. When Fe73Si11B11C3Cr2 powder is partially substituted by Fe50Co50 powder which forms a bimodal distribution, permeability decreases with, but the saturation induction increases with increasing fraction of Fe50Co50. Composites with high fraction of Fe50Co50 have good magnetic saturation and improved bias performances. Core loss is more influenced by particle size distribution. Finer Fe50Co50 powders are distributed in interstices and lead to a more loosely packed structure. On one hand, loosely packed structure increasing the interspacing of magnetic powders gives rise to low eddy current loss. On the other hand, loosely packed structure increases flowability of powders and results in low-viscosity feedstock, which can be molded with low injection pressure resulting in small internal stresses, giving rise to low core loss. As a result, hybrid SMCs with 50% fraction of Fe50Co50 powder exhibits the best comprehensive magnetic properties.