Hall–Petch behaviour of stoichiometric Fe3Al

Iron aluminides based on the compositions Fe3Al and FeAl are candidate materials for application as high temperature structural materials due to their superior oxidation and sulphidation resistance. The mechanical properties of these intermetallics can be controlled by thermomechanical treatments. The effect of high temperature thermomechanical treat-ments on the room temperature mechanical proper-ties of binary iron aluminide Fe3Al has been investigated [1]. It was noticed that the mechanical properties (especially the strengths) could be corre-lated with the grain size. This letter discusses the Hall–Petch behaviour of binary Fe3Al. A cast pancake of composition 74.72 Fe–25.28 Al (0.25) was supplied by the Defense Metallurgica