The development of a Fe 74 Si 11 B 14 Ni 1 soft magnetic powder used for SMC materials

Soft magnetic composites (SMCs) are produced by compressing together soft magnetic powders and a binding insulator material. In some applications these composites are able to replace electrical steel sheets or ferrites. Here we report on the development of an SMC produced from Fe 74 Si 11 B 14 Ni 1 alloy powder and a binding epoxy insulator. The Fe 74 Si 11 B 14 Ni 1 powder was prepared by water atomization. The surfaces and the microstructures of the amorphous and nanocrystalline powders were investigated by x‐ray photoelectron spectroscopy (XPS), x‐ray diffraction (XRD), scanning electron microscopy (SEM) and high‐resolution transmission electron microscopy (HRTEM). It was found that most of the water‐atomized Fe 74 Si 11 B 14 Ni 1 alloy powder particles that were smaller than 40 µm had an amorphous structure with small, isolated nanocrystalline grains. During annealing a completely nanocrystalline structure was obtained. Copyright © 2004 John Wiley & Sons, Ltd.