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Nanocrystalline Cu50Ni50 alloy powder was prepared by the mechanical alloying process in high-energy planetary ball mill P7 under an argon atmosphere. Structural, microstructural, morphological, and magnetic properties were followed by X-ray diffraction, scanning electron microscopy coupled with EDX analysis, and vibrating sample magnetometry. The mixing of Cu and Ni powders at the atomic level leads to the formation, after 30 h of milling, of two fcc NiCu structures having crystallite sizes of about 15.6 and 65.9 nm and close lattice parameters of about 3.5783 and 3.5794 A that would correspond to Ni 41.8Cu 58.1 (40.75 %) and Ni 40.6Cu 59.4 (59.25 %) compositions, respectively. Magnetic measurements reveal that the obtained powders are typical soft magnetic materials. According to the Mr/Ms ratio, the grains are either pseudo-single domain or multidomain.

Mechanically alloyed Fe73.5Si13.5 B 9Nb3Cu1 powders were used as feedstock materials for depositing nano/amorphous coatings by high-velocity oxy-fuel thermal spraying process. Morphology, structure, microstructure, hyperfine, and magnetic properties have been investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Mossbauer spectrometry, and vibrating sample magnetometer. The coating structure consists of bcc Fe(B)-type, bcc Fe(Si)-type, and amorphous phases. The crystallite sizes of Fe(Si) and Fe(B) solid solutions increase after spraying to about (72–82) and (48–81) nm, respectively. The Mossbauer spectrometry results reveal the presence of Fe2B boride. The squareness ratio M r/ M s and the coercivity values of the coatings decrease with increasing the number of passes.