Kinetics of reordering in a nanograined FeAl alloy

The ordered structure of Fe-40 at.%Al B2 powders was disordered and nanocrystallized using a high energy ball-milling. The reordering process of the originally nanocrystalline metastable alloy was investigated under continuous heating conditions and isothermal heat treatments by means of X-ray diffraction (XRD), differential scanning calorimetry (DSC) and magnetic measurements (TGM/VSM). Two different stages were identified and from the XRD data it was possible to associate the low temperature DSC peak and TGM drop to reordering and the high temperature DSC peak and TGM deflection to recrystallization and fully recovery of defects. The kinetics of the reordering process has been established and the possible mechanisms involved in the reordering process are discussed.