|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||High Entropy Alloys V
||Ordering Effects and Dislocation Structures in High Entropy Alloys: A Computational Approach
||Leonie Koch, Alexander Stukowski, Karsten Albe, Markus Mock
|On-Site Speaker (Planned)
The phase stability and dislocation structure of a multicomponent equimolar HEA is studied by a variance constrained semi-grandcanonical Monte-Carlo method in combination with molecular dynamics simulations. We report simulations of a random solid solution of CuNiCoFe, which is stabilized by configurational entropy at elevated temperatures. A detailed analysis of the chemical and structural order at lower temperature, however, provides evidence for the fact that HEAs evolve into multiphase alloy systems at lower temperature. We further study the motion of an initially straight dislocation line under the action of external shear stress. The dislocation line is developing a kinked structure and is locally pinned. Our simulations reveal that local disorder has a major impact on the dislocation motion. By analyzing the temperature and stress dependence of the depinning process of the dislocation line, we find significantly increased local Peierls barriers, which are one possible reason for the observed strength of HEAs.
||Planned: Supplemental Proceedings volume