About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
High-Entropy Materials: Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond VI
|
| Presentation Title |
Atomistic Modeling of Defect Energetics and Plasticity in CoCrFeMnNi Using a Moment Tensor Potential |
| Author(s) |
Mashroor Nitol, Subah Mubassira, Shuozhi Xu, Saryu Fensin |
| On-Site Speaker (Planned) |
Mashroor Nitol |
| Abstract Scope |
Machine‑learned interatomic potentials enable accurate modeling of high‑entropy alloys, overcoming empirical‑model limitations. A Moment Tensor Potential was developed for FCC CoCrFeMnNi and subsystems using a DFT dataset spanning elemental to quinary compositions. The MTP reproduced DFT elastic constants and surpassed classical potentials in shear moduli and Cauchy pressures. It generalized to non‑equiatomic CoCrFeNi alloys, capturing bulk and shear trends beyond its training domain. Free‑energy calculations predicted an FCC→HCP transition at 422 K against a DFT benchmark of 340 K. Defect energetics—including suppression of tri‑vacancy clustering—matched DFT and experiment. Short‑range order trends, notably Cr–Cr avoidance, were captured, and GSFE calculations showed SRO raises intrinsic and unstable fault energies, enhancing slip resistance. CRSS simulations of edge dislocations indicated that SRO increases CRSS across compositions, especially in CoCrNi. These results demonstrate near‑DFT accuracy for defect‑mediated behavior in complex alloys, providing a predictive framework for phase stability and plasticity in multicomponent systems. |