NSUF 25-5391: Microstructural characterization of U-10wt.%Zr specimens from MFF-2 experiment for FAST experiment benchmarking
Uranium-zirconium fuels have achieved high burn-up performance up to 19 at.% without fuel pin failure. Understanding the irradiation phenomena of U-Zr, as well as the validation of new fuel concepts is a requirement for the deployment of advanced reactors. However, neutron irradiation experiments are costly and time intensive. Consequently, newer experimental configurations were proposed to diminish the time and cost of neutron irradiation experiments. Such is the Fission Accelerated Steady-State Testing (FAST). The challenge is to verify if FAST can duplicate the irradiation phenomena historically observed in U-Zr. While there is historical U-Zr data, direct data comparison is not an adequate approach. Unavoidable differences exist due to scaling down the geometry of the specimen, with differences in the temperature and the neutron flux distribution when compared to traditional fuel geometries. Also, the disparity between data is also heavily affected by the characterization technique. Hence, validation of the FAST experiment requires comparing the data under similar irradiation conditions and characterization techniques. From the available historical specimens surveyed the MFF-2 experiment, pin 195080, axial height of 0.26 x/L cross-section corresponds well in temperature and burn-up with FAST-051. The MFF-2 specimen was irradiated to 8.2at.% burn-up with FCLT of 626ºC and PICT of 460ºC, whereas the FAST-051 was irradiated to 8.1at.% burn-up with FCLT of 591ºC and PICT of 487ºC. We propose to conduct SEM characterization of the MFF-2 specimen. The experiment requires 8 hours for re-polishing of the MFF-2 specimen, and 24 hours for SEM characterization to survey the complete cross-section with secondary electrons (SE), backscattered electrons (BSE), and energy dispersive spectroscopy (EDS). With this data, the current proposal aims to understand (1) if the FAST experiment replicates microstructural features qualitatively and quantitatively similar to that observed in historical U-Zr irradiations, and (2) if considerable differences exist, how they can be assessed.
Additional Info
| Field | Value |
|---|---|
| Awarded Institution | Purdue University |
| DOI | 10.46936/NSUF/60015374 |
| Embargo End Date | 2027-09-03 |
| Facility Tech Lead | Noé Morales |
| NSUF Call | FY 2025 RTE 2nd Call |
| PI | Nicole Rodriguez Perez |
| PIE Facilities | Irradiated Materials Characterization Laboratory |
| Project Member | Assoc. Prof. Maria Okuniewski, Associate Professor - Purdue University (https://orcid.org/0000-0003-3498-6827) |
| Project Member | Dr. Tiankai Yao, Staff Scientist and Nuclear Facility Engineer - Idaho National Laboratory (https://orcid.org/0000-0001-8330-7638) |
| Project Member | Geoffrey Beausoleil, Nuclear Fuel Engineer - Idaho National Laboratory |
| Project Member | Dr. Yachun Wang, Nuclear Engineer - Idaho National Laboratory (https://orcid.org/0000-0002-4952-3633) |
| Project Member | Miss Nicole Rodriguez Perez, Research Assistant - Purdue University (https://orcid.org/0000-0002-8958-9864) |
| Project Type | RTE |