Influence of iron powder particle size on the microstructure and properties of Fe3Al intermetallics prepared by mechanical alloying and spark plasma sintering

Fe3Al based intermetallics were prepared by mechanical alloying and spark plasma sintering (SPS), influences of iron powder particle size on the microstructure and properties of samples were investigated. The phase identification was investigated by X-ray, the surface morphology and fractography were observed by SEM. The mechanical properties such as bending strength and strain were tested. The results show that the particle size has evident effects on the sintered materials. Homogeneous and fine microstructure was obtained by super fine (2–3 μm) iron powder. The densities of samples are nearly the theoretical value of Fe3Al. The mechanical properties of sintered samples were improved. Comparing with the coarse powder, the quantity of Fe3AlC0.5 in the samples by fine powder increased, the sintered density increased 2–3%, the bending strength enhanced about twice and strain about treble.