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Powders of Fe50Al30Ni20 (wt%) are being milled in a P7 high-energy planetary ball mill to determine the effect of milling time on magnetic properties. In order to track changes in morphology and magnetic properties, SEM, magnetic measurements, and Mossbauer spectroscopy were employed during milling. Multiple phases are present; B2-(Fe, Ni)Al dominates, and Fe(Ni, Al) is second in strength. This indicates that they are paramagnetic at room temperature based on the Mossbauer effect spectra after 8 h of milling. The coercivity Hc and saturation magnetization, on the other hand, remains finite values in magnetic measurements. The CASTEP (Cambridge Serial Total Energy Package) code was used to investigate magnetic behavior further.

A nanostructured Ni50Co50 mixture was prepared by high-energy ball milling in a planetary ball mill (Frisch P7) under an argon atmosphere. Scanning electron microscopy and X-ray diffraction (XRD) have been used to study the morphology of the powder particles, microstructure, and structure evolution. Detailed analysis of the XRD patterns was performed by the MAUD program, which is based on the Rietveld method. It reveals the complete vanishing of the Co peaks after 3 h of milling, indicating the allotropic transformation of Co from hcp to fcc structure. The reciprocal dissolution of the elemental Ni and Co powders leads to the formation of a heterogeneous solid solution with two structures: fcc-Ni(Co) and fcc-Co(Ni) with relative fractions of about 76 and 20%, respectively, after 24 h of milling. Microstructural parameters such as lattice parameter, crystallite size, microstrains, dislocation density, and stacking faults have been deduced from the best Rietveld refinements. The formation kinetics of nanostructured Ni50Co50 mixture can be described by a lower Avrami parameter, n, close to 0.34.