About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
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Symposium
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Advances in Multi-Principal Element Alloys IV: Mechanical Behavior
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Presentation Title |
Harnessing Defects for Enhanced Strength in Medium Entropy Alloys |
Author(s) |
Ning Zhang, Charles Matlock |
On-Site Speaker (Planned) |
Ning Zhang |
Abstract Scope |
We employed atomistic simulations to explore how lattice defects and short-range order (SRO) influence the mechanical properties of a polycrystalline face-centered cubic CrCoNi medium-entropy alloy (MEA). Six different types of defects, including three annealing twins and stacking fault variations, along with a control modeled as random solid solutions (RSS), were analyzed. Our simulation results demonstrated that all introduced defects enhanced the RSS models' strength and modulus of toughness. Specifically, a higher density of fine annealing nano twins was observed to increase yield strength and modulus of toughness significantly. This was due to the increased inhibition of dislocation slip by twin boundaries, reducing strain accommodation by intrinsic stacking faults. The introduction of SRO produced the highest strengthening effect in the gradient-twinned model due to a reduction in partial dislocation slip at early strains. These results suggest that incorporating lattice defects through annealing can enhance the strength and toughness of CrCoNi MEAs. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Entropy Alloys, Mechanical Properties, Modeling and Simulation |