The role of pre-formed Fe2Al5 in P/M processing of Fe3Al

A stress-free sintering approach for iron aluminide powder-metallurgy (P/M) products by employing the pre-formed Fe2Al5 particles as one of starting materials is demonstrated in the present study. The processes of fabricating Fe2Al5 particles and mixing them with Fe powder, then sintering to the final Fe3Al products have been described in this work. A great amount of pores, brittle and easily broken characteristics with a relatively low melting temperature were observed in the pre-formed Fe2Al5 material. The present process exhibits the advantage of circumventing the swelling and expansion problems which are always observed in a common stress-free sintering process of an elemental Fe–Al mixture compact. The tensile properties and microstructures of various sintered Fe3Al specimens were investigated and compared. The density and room temperature tensile elongation could reach 96 and 4.8% in the thermal–mechanical treated Fe3Al P/M specimens, respectively.