About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Local Chemical Ordering and Its Impact on Mechanical Behaviors, Radiation Damage, and Corrosion
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| Presentation Title |
Atomistic Insights into the Roles of Mechanical Strain and Chemical Ordering on Molten FLiNaK Salt Corrosion of NiCr Alloys |
| Author(s) |
Hamdy Arkoub, Jia-Hong Ke, Miaomiao Jin |
| On-Site Speaker (Planned) |
Hamdy Arkoub |
| Abstract Scope |
Molten salt corrosion poses a complex challenge for structural materials, where degradation is influenced not only by alloy composition but also by internal microstructure and stress. Using reactive molecular dynamics, we investigate how applied strain and chemical ordering affect the corrosion behavior of NiCr alloys exposed to molten FLiNaK salt at 800°C. We first examine ±4% uniaxial strain on a Σ5(210) grain boundary in Ni-25at%Cr and find that tensile strain accelerates corrosion by enhancing fluorine penetration and grain-boundary diffusion. Compressive strain, in contrast, plays a protective role. To assess chemical effects, we simulate Ni-33at%Cr alloys with varying chemical order, inspired by experiments linking Ni₂Cr phases to accelerated degradation. Our results reveal that long-range ordered Ni₂Cr phases, with weaker bonding and higher atomic mobility, are more susceptible to Cr leaching and accelerated dealloying. These findings provide fundamental insight into how stress and atomic-scale ordering influence corrosion kinetics, guiding corrosion-resistant alloy design. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Nuclear Materials, Other |