NSUF 18-1151: Electron Tomography for Three-Dimensional Characterization of Intragranular Fission Product Transport in Neutron-Irradiated Silicon Carbide in TRISO Fuel
The overall goal of this project is to demonstrate the use of electron tomography in characterization of advanced nuclear fuel. This project will unveil the three-dimensional (3D) complexity of fission products transport phenomena in neutron-irradiated tristructural isotropic (TRISO) fuel. The traditional characterization of silicon carbide (SiC), a coating layer in TRISO fuel, is done via transmission electron microscopy; in this method, the structural-defect-assisted intragranular fission product transport is poorly understood due to the two-dimensionality of the imaging technique. In spite of advanced microscopy methods and modeling efforts, the microstructural stability of SiC under high temperature and neutron fluence remains controversial. Recent research effort has demonstrated that the intragranular fission product precipitation is accomplished via an interesting two-step nucleation route. In the first step, nanoscale alpha-SiC precipitates in a beta-SiC matrix unexpectedly nucleate heterogeneously at structural defects. This occurs at significantly lower temperatures compared with the usual beta-alpha transition temperature. Subsequently, alpha-SiC precipitate acts as a surrogate template for its structural and compositional transition into a fission product precipitate. The success of TRISO fuel further requires innovative characterization approaches, such as electron tomography, to fully comprehend this unexplored nucleation mechanism in the SiC layer in Advanced Gas Reactor (AGR) experiments. The ability to resolve both structural and compositional 3D information at sub-nanometer scale by electron tomography is a complementary, yet vital, addition to the present methods for AGR post-irradiation microstructural characterization.
Informație Adițională
| Cîmp | Valoare |
|---|---|
| Awarded Institution | Idaho National Laboratory |
| Embargo End Date | 2024-05-09 |
| Facility Tech Lead | Alina Montrose, Mukesh Bachhav |
| NSUF Call | FY 2018 RTE 1st Call |
| PI | Subhashish Meher |
| PI Email | [email protected] |
| PI Phone Number | 2085268960 |
| Project Member | Dr. Lingfeng He, Associate Professor - North Carolina State University (https://orcid.org/0000-0003-2763-1462) |
| Project Member | Dr. Isabella van Rooyen, Senior Technical Advisor Advanced Material Systems - Pacific Northwest National Laboratory (https://orcid.org/0000-0001-8524-938X) |
| Project Member | Dr. Subhashish Meher, Materials Scientist - Pacific Northwest National Laboratory (https://orcid.org/0000-0003-1599-4346) |
| Project Member | Dr Ahmad Alsabbagh, Assistant Professor - Jordan University of Science and Technology (https://orcid.org/0000-0001-9059-5025) |
| Project Notes | Awarded on 12/13/2017 |
| Project Type | RTE |
| RTE Number | 1151 |