Evolution of short- and long range order during milling of AlFe

The intermetallic compound AlFe in its ordered B2 phase was ground under Ar in a ball-milling device. Phase evolution is examined as a function of milling time by XRD, transmission Mossbauer spectroscopy, and DSC. Short- and long-range disorder was observed. The evolution of the long-range-order parameter and of the local atomic configurations at Fe sites with increasing milling time up to the completion of the solid state reaction is analyzed. Kinetic analysis of the reordering and recrystallization was performed under continuous heating and isothermal calorimetric regimes. Modeling of these processes is presented, as well as the estimated values of both the enthalpy and the activation energy of the reordering process. Results are compared with preceding information on related systems. (Author)