Solid state amorphization of Fe50Nb50 powders during mechanical alloying

In the current study, the progress of solid state amorphization reaction of Fe50Nb50 alloy powders starting from elemental Fe and Nb powder mixtures by mechanical alloying was investigated. Techniques including scanning electron microscopy, microhardness, X-ray diffraction, differential thermal analysis, and extended X-ray absorption fine structure (EXAFS) were used to investigate the as-milled powders as a function of milling time. The intensities of the crystalline peaks of the elemental powders gradually decreased as the milling time increased and, after 15 hours of milling, an amorphous-indicating broad peak formed. The radial distribution functions obtained from Fourier transformation of EXAFS spectra reveal that there are differences in local atomic structure after prolonged milling. Combined with the information from various techniques, the amorphization process of Fe50Nb50 during MA is better understood.