TENSILE AND IMPACT PROPERTIES OF DIRECTIONALLY SOLIDIFIED FE-40AL INTERMETALLIC

The mechanical properties of a DS Fe-40Al intermetallic compound have been evaluated by tensile and impact tests from room temperature to 800 C. Yield strength reaches a peak at 600 C, at which a smooth yield point occurs. Directional solidification provides an improvement of tensile ductility at all temperatures, although the yield strength remains the same as that of conventional castings. A Charpy impact energy of 76 J was measured at room temperature, but the value decreased with the increasing testing temperature. This negative temperature dependence of Charpy impact energy may be caused by a transition of slip systems.