Atomization of Al-rich alloys: Three paradigmatic case studies

In this work we present our results on three aluminum rich alloys processed by atomization: Al90Fe5Nd5, Al93Fe3Cr2Ti2, and Al68.5 Ni31.5, 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, Al68.5 Ni31.5, 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.