Preparation of nanocrystalline Fe–Ni powders by mechanical alloying used in soft magnetic composites

This paper focuses on the preparation of nanocrystalline Fe–Ni powders by mechanical alloying method, which can be used in soft magnetic composites. Fe–10 wt% Ni and Fe–20  wt % Ni alloys were prepared using a high-energy ball mill. The magnetic properties of samples were measured by a B–H curve analyzer and microstructures of the samples were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The bcc Fe(Ni) phase formation was identified by XRD and completed after 45 h of milling. It was found that higher milling time resulted in, larger lattice parameter, higher microstrains and smaller crystallite sizes. Also, results showed that with increasing the milling time, coercivity increased and saturation intrinsic flux density firstly increased noticeably and then decreased in higher milling times (>70 h).