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arXiv · 2108.10010

Orientation-related twinning and dislocation glide in a Cantor High Entropy Alloy at room and cryogenic temperature studied by in situ TEM straining

Daniela Oliveros·Anna Fraczkiewicz·Antonin Dlouhy·Chen Zhang·Hengxu Song·Stefan Sandfeld·Marc Legros
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Abstract

In situ straining experiments were performed in a TEM on an equimolar CoCrFeMnNi (Cantor) high entropy alloy at room and cryogenic temperature. Perfect and partial dislocation activity were recorded in both cases. Twinning directly follows the development of partial dislocation shearing that has various origins (perfect dislocation splitting, anchoring). It is shown that, although twinning is more frequently observed at liquid nitrogen temperature, its prevalence depends mainly on crystal orientation. As a result, twinning and perfect dislocation plasticity are likely to occur jointly in random oriented polycrystals, even at early stages of deformation.

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Daniela Oliveros, Anna Fraczkiewicz, Antonin Dlouhy, Chen Zhang, Hengxu Song, Stefan Sandfeld, Marc Legros. 2021-08-23. Orientation-related twinning and dislocation glide in a Cantor High Entropy Alloy at room and cryogenic temperature studied by in situ TEM straining. https://doi.org/10.1016/j.matchemphys.2021.124955

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