About this Abstract |
| Meeting |
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Presentation Title |
Microstructural Characterization of Irradiated Metallic Fuel Using Complementary EPMA, SEM, and TEM Analyses |
| Author(s) |
Mitchell L. Mika, Karen Wright, Allison Probert, Luca Capriotti, Assel Aitkaliyeva |
| On-Site Speaker (Planned) |
Mitchell L. Mika |
| Abstract Scope |
Metallic fuels undergo significant restructuring in response to thermal and chemical potential gradients during irradiation, leading to formation of distinct compositional regions. Current models of constituent redistribution assume that plutonium does not redistribute and that phase boundaries can be predicted using elemental composition and equilibrium phase diagrams, however recent works using electron probe microanalysis (EPMA) and transmission electron microscopy (TEM) have challenged the validity of these assumptions. In this work, we characterize an EBR-II irradiated U-19Pu-6Zr sample using EPMA, SEM, and TEM to examine these assumptions at multiple length scales. The results show that plutonium redistributes during operation in the same direction as zirconium, although radial plutonium variations are much smaller than those of zirconium. Additionally, differences were found between the phases predicted by ternary phase diagrams and the phases identified using TEM selective area electron diffraction (SAED), showing that equilibrium phase diagrams are not suitable for predicting phases in the far-from-equilibrium system. These results demonstrate the need for additional experimental characterization of irradiated metallic fuels to produce a more complete physical understanding of constituent redistribution. |
| Proceedings Inclusion? |
Undecided |