In-situ precipitation of Al2O3 and κ-Fe3AlC0.5 in iron aluminides through spark plasma sintering: Microstructures and mechanical properties

Iron aluminides are ordered intermetallic alloys which offer good resistance to corrosion and sulfidation. At the same time, their Achillesʹ heel is low ductility at room temperature and sometimes they have poor mechanical properties. By means of mechanical alloying and spark plasma sintering (MA–SPS) it is possible to obtain bulk nanostructured iron aluminides which show high hardness and high yield stress. s work we present the production of nanostructured powders and their consolidation through spark plasma sintering. The inevitable use of methanol as processing control agent (PCA) leads to a supersaturation in carbon and oxygen of the milled powder and a consequent in-situ precipitation of carbides and oxides during SPS. The presence of carbides, oxides and a nanostructured matrix leads to high mechanical properties with hardness 5.20 ± 0.05 GPa and a yield stress of 1305 MPa.