| Abstract Scope |
This presentation will discuss the work of the author with Easo George over a 17 year period on the mechanical properties of the B2 compound FeAl. Two dramatic features of the mechanical properties of FeAl will be emphasized, environmental embrittlement and the yield anomaly (increasing strength with increasing temperature), including the effects of boron and aluminum content on these phenomena. Both the room temperature ductility and yield strength of FeAl are affected by the presence of water vapor, which reacts with the aluminum to produce embrittling atomic hydrogen. Thus, the elongation to failure depends strongly on strain rate. A model, developed by George and Baker, for the yield anomaly based on vacancy strengthening will be outlined along with a comparison of predictions of the model with experiments Lessons drawn from the work on FeAl will be applied to current studies on high entropy alloys. |