About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Materials and Chemistry for Molten Salt Systems
|
| Presentation Title |
Atomistic Insight into Chromium Speciation, Transport, and Oxide Interactions in Molten Eutectic NaCl-MgCl2 Salt |
| Author(s) |
Henry Sochima Ezeaku, Ximeng Wang, Yongfeng Zhang |
| On-Site Speaker (Planned) |
Henry Sochima Ezeaku |
| Abstract Scope |
Molten NaCl-MgCl2 salts are promising heat-transfer fluids for secondary loops of molten salt reactors. However, the salt’s corrosive nature can dissolve structural alloys, e.g., NiCr, by leaching chromium (Cr) into the molten salt. Once dissolved, Cr exhibits oxidation states whose speciation and transport dictate macroscopic corrosion mechanisms. This study utilized ab initio molecular dynamics simulations to investigate the solvation and transport properties of Cr0, Cr2+, and Cr3+ in eutectic NaCl-MgCl2 salt at 900 K. Structural, dynamic, and transport analyses revealed that higher oxidation states form more stable coordination complexes, reducing Cr diffusivity while decreasing corner-sharing in favor of edge and face sharing motifs. Further simulations evaluated oxide impurity interactions, revealing that Cr2+ strongly coordinates with oxygen to form stable CrO local structures characterized by dominant charge-transfer ionic behavior. These atomistic insights reveal Cr speciation mechanisms, crucial for controlling long-term alloy corrosion. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Modeling and Simulation, Nuclear Materials, High-Temperature Materials |