Atomization of Al-rich alloys: Three paradigmatic case studies

Highlights: • Al₉₀Fe₅Nd₅ amorphous and nanocomposite show yield strength of >700 MPa at 25 °C. • Al₉₃Fe₃Cr₂Ti₂ forms quasicrystals, consolidated bars retain UTS of 280 MPa at 300 °C. • Al_68.5Ni_31.5 particles can be tailored to increase its catalytic activity. In this work we present our results on three aluminum rich alloys processed by atomization: Al₉₀Fe₅Nd₅, Al₉₃Fe₃Cr₂Ti₂, and Al_68.5 Ni_31.5, for structural and functional applications. Amorphous and a nanocomposite microstructure, formed by nanocrystals of α-Al embedded in a remaining amorphous matrix, are obtained in the atomized Al₉₀Fe₅Nd₅ powder particles. Bars produced by extrusion of this powder present yield strength above 700 MPa. Atomized Al₉₃Fe₃Cr₂Ti₂ powder particles contain a high proportion of quasicrystalline precipitates, stable up to 500 °C. At 300 °C, Al₉₃Fe₃Cr₂Ti₂ extruded bars present ultimate tensile strength as high as 280 MPa. Raney alloy, Al_68.5 Ni_31.5, is of high interest as a catalyst. When it is atomized, the particles present a fine dendrite microstructure, which is very suitable for catalyst reactions once the Al rich phases have been leached away.