High-temperature deformation behaviour of Fe3Al

High-temperature deformation behaviour and workability have been determined for an Fe3Al-based alloy. The composition of the alloy (Fe-16.5Al-5.5Cr-l.0Nb-0.05C) was one developed at Oak Ridge National Laboratory. Compression tests of samples from as-cast ingots and from hot-rolled + annealed plate were carried out over a range of temperatures (900-1200°C) and strain rates (10-3-10 s-1)-Three types of deformation behaviour are observed: (I) partial dynamic softening; (II) dynamic recrystallization; and (III) dynamic recrystallization with grain coarsening. The data are fitted to a single constitutive equation which describes the temperature and strain rate dependence of flow stress. The alloy is resistant to flow localization, but workability is limited by tensile edge cracking.