A STUDY OF NANOCRYSTALLINE IRON AND ALUMINUM METALS AND FE3AL INTERMETALLIC BY MECHANICAL ALLOYING

Pure iron and aluminium powders and a mixture of composition Fe75Al25 were treated mechanically in a high-energy mill for up to 40 h. X-ray diffraction and analytical transmission electron microscopy were coupled to elastic energy dissipation and dynamic Young's modulus measurements to study the structural transformation of the specimens induced by the mechanical treatment. A quantitative comparison between the structural behaviour of the pure elements and of the mixture was carried out, The role of the parameters such as the composition, the grain size and the activation energy during the process was examined in relation to the competing mechanisms of plastic deformation and recovery.