NSUF 25-5562: Fission gas release in UO2 and doped UO2 and the effects of solid fission products
The objective of this project is to enhance the safety and performance of LWRs and other advanced reactor designs by gaining a fundamental understanding of FGR mechanisms. We propose the following hypotheses: (1) Under SS conditions, FG primarily releases via GB diffusion in the rim region. FG diffusional release increases with decreasing grain size and is influenced by Cr2O3 dopants; and (2) SFP precipitates pin FG bubbles, suppressing their coalesce and reducing FGR rate. We will use surrogate UO2 fabricated by advanced Spark Plasma Sintering (SPS) to realize grain size, dopant, and SFP controls, for systematic investigation of microstructural effects on FGR. Through this super RTE, we request Xe implantation and post irradiation / testing examination. The Xe implanted samples will be testef for FGR at the PI’s lab using an innovative approach of Thermogravimetry (TG), Differential Scanning Calorimetry (DSC), and Mass Spectroscopy (MS). The microstructural characterization combined with TG/DSC-MS data will test our hypotheses and advance our understandings of the FGR process and mechanisms as a function of fuel microstructure. This knowledge will lead to parameterization of FG diffusional properties and FG-SFP interactions, and the development of phase-field mechanistic models. Ultimately, the developed mechanistic models will be implemented into the fuel performance code of BISON.
Additional Info
| Field | Value |
|---|---|
| Awarded Institution | Oregon State University |
| DOI | 10.46936/NSUF/60015725 |
| Embargo End Date | 2028-01-22 |
| Facility Tech Lead | Lin Shao, Mukesh Bachhav |
| Irradiation Facilities | Accelerator Laboratory |
| NSUF Call | FY 2025 Super RTE Call |
| PI | Tianyi Chen |
| PIE Facilities | Microscopy and Characterization Suite |
| Project Member | Dr Jie Lian, Professor - Rensselaer Polytechnic Institute (https://orcid.org/0000-0002-9060-8831) |
| Project Member | Dr. Tianyi Chen, Assistant Professor - Oregon State University (https://orcid.org/0000-0003-2880-824X) |
| Project Type | RTE |