About this Abstract |
| Meeting |
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Presentation Title |
Characterizing Thermal Pd Transport in SiC-Coated Tristructural Isotropic Particles |
| Author(s) |
Sabiha Younus, Jerod Siguaw, TyRon Jones, Mira Khair, Patrick Warren, Elizabeth Sooby |
| On-Site Speaker (Planned) |
Sabiha Younus |
| Abstract Scope |
The Tristructural Isotropic (TRISO) particle is a composite fuel particle with multiple layers providing structural integrity while preventing the escape of fission products. Palladium is a fission product that has been identified in the inner pyrolytic carbon (PyC) layer to SiC layer interface and within the SiC layer of TRISO particles. Migration of Pd to the SiC layer has also been associated with U contamination within the SiC grain boundaries. Excessive Pd accumulation in the PyC and SiC layers ultimately leads to reduced performance and eventual failure of the TRISO particle. The mechanism of this Pd transport has still not been fully captured, and further investigation is needed. In this study, Pd-SiC diffusion couples were annealed at 900°C, 1000°C, and 1100°C for 1, 4, 8, 16, and 32 hours at each temperature. Scanning electron microscopy, energy-dispersive X-ray spectroscopy and Raman spectroscopy were used to characterize Pd diffusion and compounds formed within the post-anneal microstructure. This experiment was repeated with surrogate TRISO particles (sourced from Oak Ridge National Laboratory) coated with Pd using physical vapor deposition. Electron backscatter diffraction was used to examine the bulk SiC grain orientation, while hardness was evaluated using micro- and nanoindentation. The resulting corrosion data supports the understanding of how the mechanical properties of SiC may influence Pd transport within TRISO particles. |
| Proceedings Inclusion? |
Undecided |