About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
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Symposium
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Advances in Multi-Principal Element Alloys III: Mechanical Behavior
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Presentation Title |
Atomistic Simulation Study on the Short-range Chemical Ordering and Dislocation Behaviors in the Refractory NbTaTiV High-Entropy Alloy |
Author(s) |
Chin-Lung Kuo |
On-Site Speaker (Planned) |
Chin-Lung Kuo |
Abstract Scope |
We employed first-principles calculations and MEAM modeling to investigate the short-range chemical ordering and dislocation behaviors in the NbTaTiV RHEA. Our calculations showed that the thermodynamic stability of this HEA can be greatly enhanced by increasing the number of Ta-V pairs while decreasing the number of V-V/Ta-Ti pairs within the alloy, indicating the tendency to form short-range chemical ordering in the NbTaTiV RHEA. Our calculations further showed that the average core energy of the dislocations in RHEA is substantially lower than their constituent elements, indicating a relatively higher dislocation density with reduced mobility in RHEA than in other BCC metals. It was also found that the average dislocation core energy in RHEA with local chemical ordering is comparable to that within the SQS structure. However, some core structures with extremely low energies were identified, which can effectively hinder the motion of dislocation to enhance the mechanical strength of RHEA. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, Mechanical Properties, High-Entropy Alloys |