|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||High Entropy Alloys IV
||Effects of Chemical Composition on Mechanical Behavior of CoCrFeMnNi Alloys: The Origins of High Strength of A3S Grade of Alloys
||Anna Fraczkiewicz, Michal Mroz, Matthieu Lenci, Andras Borbely, Xavier Sauvage
|On-Site Speaker (Planned)
An optimal non-equiatomic proportion of metals in CoCrFeMnNi family leads to spectacular increase of mechanical resistance, in comparison to equiatomic alloys (EA) of the same family. The A3S grade of alloys (this conference) shows a YS value twice as high as in EA, with conserved high ductility level, but the work hardening parameter strongly decreased. The mechanisms of this behavior remain unidentified. In this paper, different mechanisms of plastic deformation are discussed for A3S and EA alloys. Several hypotheses could be rejected: no significant fluctuations of local chemical compositions have been observed (APT measurements); no martensitic transformation was identified; no more that the presence of (nano)twins. The dislocations structure (TEM observations) seem to be similar in both alloys. Therefore, as the A3S alloys (in contrast to EA) show a great ability to create and to stabilize nanostructures, this feature is proposed as being responsible for the mechanical behavior of A3S.
||Planned: A print-only volume