Effect of the alloying element chromium on the room temperature ductility of Fe3Al intermetallics

The effect of the alloying element chromium on the room temperature ductility of Fe3Al intermetallics has been investigated by considering its effect on (1) intrinsic ductility related to the microstructure, etc.; (2) extrinsic ductility related to the surface state. Based on the dissociation energy, the effect of atom interactions on the room temperature ductility is discussed after considering the site occupation of the substitutional element Cr at sublattice sites in DO3 type stoichiometric Fe3Al intermetallics. The deduced results are in good agreement with those obtained from tensile tests of the samples with different structure and surface states in air and vacuum, and the observation of slip traces and APB trails left by imperfect dislocation slipping.