Magnetic behavior of SmCo3Cu2/alpha-Fe nanocomposite obtained by mechanical milling
Résumé
SmCo3Cu2/alfa-Fe nanocomposites have been obtained by mechanical milling (MM) of a SmCo3Cu2+30wt% Α-Fe mixture and subsequent annealing. The progressive structural modifications were checked by X-ray diffraction (XRD). The width of the diffraction peaks of the hard magnetic phase was found to increase with milling time and the peaks almost disappeared after 9 h of milling. The characteristic diffractions peaks of the SmCo5-type phase could be restored by applying an appropriate heat treatment. The magnetic behavior of the SmCo3Cu2/ alfa -Fe nanocomposite was studied versus milling and annealing conditions. A dramatic decrease in both the coercivity and the remanence was observed after milling. Considering the importance of the microstructure for the coercivity development in the SmCo3Cu2 bulk alloys, the hard magnetic properties of the SmCo3Cu2/alfa-Fe nanocomposite are discussed in comparison with those characterizing bulk SmCo3Cu2.