BEHAVIOR OF Mg AND ITS EFFECT ON MECHANICAL PROPERTIES OF CAST Fe3Al ALLOYS

Proper addition of 0.002 wt-% Mg to cast FeAl alloy may obviously improve the room andhigh temperature tensile properties.Auger spectra show that Mg segregates near grainboundaries as very thin layers.Observation under TEM reveals that a suitable amount of Mgenhances ability of cooperative internal deformation so that the dislocations will ease the con-tinuous slip deformation through grain boundaries.The fracture feature of FeAl alloy is oftransgranular cleavage at room temperature and cracks initiate at grain boundaries.