About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
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Symposium
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Local Ordering in Materials and Its Impacts on Mechanical Behaviors, Radiation Damage, and Corrosion
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Presentation Title |
Short-range Order Effects on Dislocation Mobilities in High-entropy Alloys from Atomistic Simulations |
Author(s) |
Sheng Yin, Anas Abu-Odeh, David Olmsted, Jun Ding, Wenqing Wang, Flynn Walsh, Robert Ritchie, Mark D. Asta |
On-Site Speaker (Planned) |
Mark D. Asta |
Abstract Scope |
We present results of atomistic simulations for core structures and mobilities of edge and screw dislocations in refractory high-entropy alloys. The work focuses specifically on understanding of the role of chemical short range order (SRO) on the energy landscapes and resulting dislocation mobilities. We present results for the MoNbTaW system (and its subsystems), which displays excellent high-temperature strength but poor tensile ductility. The mobility of edge dislocations is found to be enhanced by the presence of SRO, while the rate of double-kink nucleation in the motion of screw dislocations is reduced. The results are discussed in the context of known behavior in elemental bcc refractory metals, and binary concentrated solid solutions. They are also discussed in the context of anisotropy of dislocation mobility, which has been suggested as a key contributing factor of intrinsic ductility. Research supported by the DOE-BES Damage Tolerance in Structural Materials program. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Entropy Alloys, High-Temperature Materials, Computational Materials Science & Engineering |