Plastic Deformation Behavior of Differently Oriented Fe-35wt.Cr Alloy Single Crystals Containing Cr-rich Precipitates under Uniaxial Compression

摘要

The plastic deformation behavior of the [149] and [014] Fe-35wt.%Cr alloy single crystals containing fine Cr-rich precipitates were investigated under uniaxial compression. The compressive flow behavior is slightly sensitive to the crystallographic orientation. These two oriented crystals exhibit a clear yield plateau in their compressive stress-strain curves, but the yield plateau of the [014] crystal is somewhat shorter than that of the [149] crystal. As the compressive strain is lager than a certain critical value, e.g., ～13% and ～18% for the [014] and [149] crystals, respectively, the work hardening rate for both two orientations decreases obviously, but the decrease in work hardening rate is more remarkable for the [014] crystal rather than the [149] crystal. These phenomena are discussed to be all related to the interactions between moving dislocations and fine Cr-rich precipitates, and the interaction intensity depends strongly on the orientation. Careful observations of slip deformation characteristics and dislocation structures well provide supports for the explanations to the macroscopic compressive plastic flow behavior.