NSUF 25-5402: Microstructural characterization of structural alloys under combined proton-irradiation and molten salt corrosion
Molten salt reactors (MSRs) are promising advanced reactor designs due to their excellent heat transfer capabilities, low vapor pressure, and high thermal stability. However, the highly corrosive nature of molten salts, aggravated by irradiation and salt impurities, poses significant challenges to the integrity and longevity of reactor materials. This study will perform unique simultaneous in-situ irradiation-corrosion experiments, subjecting structural alloy foils of Inconel 625 and AISI 316L to the combined action of proton-irradiation and molten salts at high temperatures. The chloride salt LiCl-KCl eutectic, with and without the oxidizing impurity-additive EuCl3, will be used to mimic fission products from reactor fuel burnup. Subsequent post-irradiation examination (PIE) work of the procured samples will include focused-ion beam analysis and advanced (scanning) transmission electron microscopy ((S)TEM) characterization, both available at Idaho National Laboratory (INL). The primary objectives are to investigate the formation of irradiation-induced defects, understand their impact on corrosion processes near the molten salt interface, and identify the complex mechanisms that govern the irradiation-corrosion performance of the alloys. If successful, this research will be able to answer the research hypothesis that: proton-irradiation activates alternate corrosion mechanisms in structural alloys exposed to impurity-additive molten salts, which can be highlighted through microstructural characterization of the molten salt-substrate interface layer. In achieving this, this research aims to fill a critical knowledge gap regarding the synergistic effects of irradiation and corrosion, potentially leading to the development of more resilient materials for MSRs, and thus work towards the broader goal of developing more sustainable and safer nuclear energy technologies.
Additional Info
| Field | Value |
|---|---|
| Awarded Institution | Idaho National Laboratory |
| DOI | 10.46936/NSUF/60015378 |
| Embargo End Date | 2027-09-03 |
| Facility Tech Lead | Adrien Couet, Mukesh Bachhav |
| Irradiation Facilities | University of Wisconsin Ion Beam Laboratory |
| NSUF Call | FY 2025 RTE 2nd Call |
| PI | Aaron Penders |
| PIE Facilities | Microscopy and Characterization Suite |
| Project Member | Professor Adrien Couet, Assistant Professor - University of Wisconsin (https://orcid.org/0000-0002-7330-5150) |
| Project Member | Dr Kaustubh Bawane, Postdoctoral Research Associate - Idaho National Laboratory |
| Project Member | Dr Aaron Penders, Postdoctoral Research Fellow - Idaho National Laboratory (https://orcid.org/0000-0002-1588-6532) |
| Project Type | RTE |