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Nanocrystalline FeAl alloy samples were prepared by mechanical alloying process using planetary high-energy ball mill. The alloy formation and different physical properties were investigated as a function of milling time, t, (in the 0-24 h range) by means of X-ray diffraction technique, scanning electron microscopy (SEM), energy dispersive X-ray, and Mössbauer spectroscopy. The complete formation of bcc-FeAl solid solution was observed after 4 h of milling. The lattice parameter quickly increased to a maximum value of 0.291 nm within the first hours of 12 h of milling, then decreased to a value of 0.2885 nm after 24 h. The grain size decreased from 55 to 10 nm, while the strain increased from 0.18 to 0.88%. Grain morphologies at different formation stages were observed by SEM. The Mössbauer spectrum showed the presence of a singlet and sextet after 4 h of milling. The singlet indicated the presence of paramagnetic phase characteristic of A disordered structure and the sextet with a mean hyperfine field, 〈 H〉, of 21 T was indicative of ordered DO structure. After 8 h of milling, the paramagnetic phase disappeared allowing the appearance of a sextet. For the higher milling time, i.e., 24 h, the Mössbauer spectrum was analyzed with two components. The first with 〈 H〉 equal to 29.9 T and the second with a 〈 H〉 value of 10.25 T. [ABSTRACT FROM AUTHOR]

This study aims to corroborate experimental studies in mechanical alloying by theoretical studies, particularly the calculation of the contact temperature at the impact point of the balls, basing on the mathematical model of a compact powder between two colliding balls. Indeed, within this study, we show the influence of some geometrical, dynamic, and thermophysical parameters on the variation in the contact temperature of balls and Al and Ti powders inside a vial of planetary ball mill. [ABSTRACT FROM AUTHOR]

The Fe60Co40 alloys were prepared by mechanical alloying of the Fe and Co powders using a high-energy ball mill. They were studied with respect to phase formation and magnetic properties using x-ray diffraction, scanning electron microscopy, and measurements of coercivity and remanence (Br). The evaluation of Fe lattice parameters during milling showed that formation of a body-centered cubic solid solution occurred by mechanical alloying after 12 h of milling. Intensive milling of Fe-Co powders results in a nonequilibrium microstructure characterized by grain refinement to a minimum of 10-13 nm and the introduction of internal strain up to 0.5%. [ABSTRACT FROM AUTHOR]