Mechanical alloying method was used to synthesise powders of iron with tungsten and niobium. Mössbauer spectroscopy and X-ray diffraction have been applied to monitor the progress in solid-state reactions. In the case of Fe-W system, exhibiting a positive heat of mixing, no trace of amorphization was observed for 20 and 33 at.% of W, as the calculations of phase diagram (CALPHAD) method suggest. During the mechanical alloying process, two solid solutions Fe(W) and W(Fe) were obtained. Mössbauer measurements allowed to recognise the Fe(W) solid solution as a ferromagnetic phase, while the W(Fe) solid solution as a paramagnetic one. In the case of Fe-Nb system, exhibiting a negative heat of mixing, single phase amorphous alloys were synthesised during mechanical alloying of iron with 48 and 64 at.% of Nb. For both investigated compositions, the final products of mechanical alloying processes were amorphous paramagnetic alloys.
Mechanical alloying was used to prepare Co_{40}Fe_{60}, Co_{60}Fe_{35}Ni_{5}, Co_{40}Fe_{45}Ni_{15}, and Co_{40}Fe_{35}Ni_{25} alloys from the elemental powders. As X-ray diffraction studies proved the final products of milling were the solid solutions with bcc or fcc lattice and the average grain size between 20 and 50 nm. After heating of the alloys up to 993 K, the mixtures of two solid solutions with bcc and fcc lattices were formed in the case of Co-Fe-Ni alloys. Thermal treatment did not influence the type of the lattice of Co_{40}Fe_{60} alloy. The Mössbauer spectroscopy revealed hyperfine magnetic field distribution ranged from 33 to 38 T for Co_{40}Fe_{60} alloy and from 30 to 37 T for Co-Fe-Ni alloys. In the case of two-phase alloys, distributions were decomposed into two simple Gaussian functions using the numerical fitting. Magnetic measurements allowed to determine the effective magnetic moments and the Curie temperatures of the obtained alloys.
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