NSUF 26-5644: Nanoscale feature stability and irradiation response in GRX-810 at elevated temperatures
This project aims to determine the high-temperature irradiation stability limits of Y₂O₃ nano-oxide dispersions in GRX-810, a NiCoCr-based solid-solution alloy developed for extreme environments. The hypothesis is that irradiation at elevated temperatures relevant to advanced nuclear systems will promote dynamic recovery processes that drive dispersed Y₂O₃ nano-oxides to reprecipitate into smaller, denser defect sinks. This is expected to suppress void swelling and stabilize the microstructure. While GRX-810 has demonstrated exceptional high-temperature creep life, the stability and evolution of its nano-oxide dispersion under irradiation at reactor-relevant temperatures remain unknown, limiting its qualification for deployment.
The proposed work will employ ex situ ion irradiation experiments at the Michigan Ion Beam Laboratory using 6 MeV Fe²⁺ ions to a final dose of 50 dpa at a dose rate of ~1×10⁻³ dpa/s. Irradiations will be conducted at room temperature, 427 °C, 827 °C, and 1093 °C using a PID-controlled high-temperature irradiation stage capable of maintaining stable temperatures up to ~1200 °C. This matrix is designed to identify the crossover temperature between nano-oxide stability and instability under irradiation. Post-irradiation microstructural characterization will be performed using TEM and STEM-EDS to quantify nano-oxide size distributions, number densities, and irradiation-induced defect structures.
If successful, this research will advance the state-of-the-knowledge by providing the first systematic dataset on irradiation-driven nano-oxide evolution in GRX-810 at reactor-relevant temperatures. The results will establish mechanistic links between irradiation temperature, nano-oxide stability, and defect sink efficiency, addressing a critical gap in understanding radiation tolerance in additively manufactured oxide-strengthened multi-principal element alloys.
The expected period of performance is ~3 months. The anticipated scientific outcome is the identification of irradiation-driven stability limits for Y₂O₃ dispersions in GRX-810, providing data necessary to define operational envelopes, inform materials qualification strategies, and guide future studies involving multi-ion irradiation, in situ experiments, and irradiation-informed creep modeling for advanced nuclear systems.
Additional Info
| Field | Value |
|---|---|
| Awarded Institution | University of Michigan [UM] |
| DOI | 10.46936/NSUF/60017665 |
| Embargo End Date | 2028-04-22 |
| Facility Tech Lead | Kevin Field |
| Irradiation Facilities | Michigan Ion Beam Laboratory |
| NSUF Call | FY 2026 RTE 1st Call |
| PI | Hannah Hutton |
| PIE Facilities | Michigan Center for Materials Characterization |
| Prep Facilities | Michigan Ion Beam Laboratory |
| Project Member | Dr. Kevin Field, Associate Professor - University of Michigan (https://orcid.org/0000-0002-3105-076X) |
| Project Member | Mr. Matthew Lynch, PhD Candidate - University of Michigan (https://orcid.org/0009-0008-9878-7871) |
| Project Member | Mr. Kaiser Aguirre, Materials and Processes Engineer - NASA Glenn Research Center (https://orcid.org/0000-0002-1059-5605) |
| Project Member | Ms. Hannah Hutton, PhD Candidate - University of Michigan (https://orcid.org/0009-0003-4054-2576) |
| Project Type | RTE |