About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
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Phase Transformations and Microstructural Evolution
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Presentation Title |
Negative Strain Rate Sensitivity in Al0.3CoCrFeNi High Entropy Alloy during hot deformation |
Author(s) |
Ji-Woon Lee, Kwang Tae Son, Gian Song, Junhee Han, Chulwoong Han, Hyoseop Kim |
On-Site Speaker (Planned) |
Ji-Woon Lee |
Abstract Scope |
This study investigates the deformation behavior of coarse-grained (CG) Al0.3CoCrFeNi alloy under hot compression, revealing notable strain rate sensitivity (SRS) and dynamic strain aging (DSA) phenomena. DSA is observed at temperatures between 1223 K and 1373 K, exclusively at lower strain rates (0.5 s-1 – 1 s-1), while higher strain rates (≥ 5 s-1) exhibit DSA absence. Non-compact {112} slip activation on dislocation forest structures is proposed as the driving force behind DSA. Negative SRS behavior at 1223 K is attributed to Ni-Al cluster-based solid solution strengthening. Activation energy calculations highlight lattice diffusion and partial dislocation constriction as contributors to hot deformation. Consistency is observed in the activation volume (V*) calculation, indicating dislocation forest formation (127 – 519·b3, b = Bureger’s vector), diminishing to 22 – 46·b3 upon DSA initiation. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Entropy Alloys, Characterization, Shaping and Forming |