Amorphization of Al50(Fe2B)30Nb20 Mixture by Mechanical Alloying

An amorphous Al₅₀(Fe₂B)₃₀Nb₂₀ powder mixture was prepared by mechanical alloying in a high-energy planetary ball-mill under argon atmosphere. Morphologic, microstructural, and structural changes during the milling process were followed by scanning electron microscopy and X-ray diffraction. Rietveld analysis of X-ray diffraction patterns was used to follow the solid-state amorphization transformation during the milling process of the prepared powder. The reaction between elemental Al, Fe₂B, and Nb powders leads to the formation of the Al(Fe,B) and Al(Fe,Nb,B) solid solutions after 4 and 6 hours of milling, respectively. An amorphous structure is achieved after 20 of milling. These amorphous powders are crystallized on further milling time (36 hours). The observation by scanning electron microscope shows a phenomenon of fracturing followed by compaction of the powder particles.