About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Ceramics and Ceramic-Based Composites for Nuclear Applications III
|
| Presentation Title |
Mesoscale modeling of restructuring in high burnup UO2 fuel |
| Author(s) |
Sudipta Biswas, Aagesen Larry K |
| On-Site Speaker (Planned) |
Sudipta Biswas |
| Abstract Scope |
In nuclear fuel, regions exposed to extended burnup undergoes restructuring leading to formation of a refined grain structure that generates the risk of performance degradation and fragmentation. Here, we aim to simulate the restructuring behavior observed in different regions of high burnup fuel, providing a restructuring model for the dark zone and rim region of high-burnup UO2 fuel. We employed a grand-potential-based phase-field model to concurrently evaluate subgrain formation and the growth of fission bubbles within the fuel. An energy-based subgrain formation criterion was introduced to simulate the restructuring process. Subgrain formation was observed to begin around existing fission gas bubbles and proceed toward triple junctions, grain boundaries, and grain interiors. Microstructures corresponding to the dark zone and rim region can be obtained by parameterizing the model with the appropriate defect production rate, as determined based on the burnup rate and temperature. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Ceramics, Nuclear Materials, Modeling and Simulation |