Effect of aluminium addition on the structural properties of nanostructured Fe50Co50 alloy

Nanostructured Fe50Co50 and (Fe50Co50)80Al20 powders were obtained by mechanical alloying in a high-energy planetary ball mill under argon atmosphere. Structural and microstructural changes during the milling process were followed by X-ray diffraction using the Maud program which is based on the Rietveld method. For the Fe50Co50 powders, the non-homogeneity of the α-Fe(Co) solid solution is evidenced by the existence of two bcc structures having nearly the same lattice parameter but different crystallite sizes, microstrains and proportions. The Al addition leads, above 6 h of milling, to the formation of a disordered Fe(Co, Al) solid solution and B2 AlCo nanophase (CsCl type).