Fe-Si-B-P-C-Cu nanocrystalline soft magnetic powders with high B s and low core loss

The magnetic properties of Fe-Si-B-P-C-Cu nanocrystalline powders were investigated. Fe-Si-B-P-C-Cu powders with a mostly amorphous structure were prepared by an atomization method. The atomized powders were annealed in inert gas atmosphere for nanocrystallization. The Fe84.8Si0.5B9.4P3.5C1Cu0.8 nanocrystalline powder exhibits high Bs of 1.76T, which is appreciably higher than that of conventional Fe-based amorphous powders (1.3 - 1.5 T) and close to that of Fe3.5Si4.5Cr (1.86T) crystalline one. The magnetic loss of toroidal core made of the Fe84.8Si0.5B9.4P3.5C1Cu0.8 nanocrystalline powder is also the lowest compared to that of amorphous and crystalline counterparts. This result indicates that Fe-Si-B-P-C-Cu nanocrystalline powders could contribute in efficiency-improvement as well as miniaturization of soft-magnetic cores.