Effect of Aluminum Addition on Ductility and Yield Strength of Fe3Al Alloys with 0.5 wt % TiB2

Abstract

AbstractStudies have been conducted of the mechanical properties of Fe3Al alloys containing 24 to 30 at.% Al, to which 0.5 wt% TiB2 was added for grain refinement. In tensile tests conducted at room temperature, it has been found that, as the aluminum content is increased, the yield strength decreases sharply from 760 to 310 MPa. The decrease in yield strength is accompanied by a four-fold increase in room-temperature ductility. Ordered iron aluminides (containing no disordered α phase) showed a clear increase in yield strength with temperature above 300°C. Their strength reached a maximum around 600°C, above which it decreased sharply. All these results will be discussed and correlated with stability of superlattice dislocations as a function of aluminum content.