About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Metallic Nuclear Fuel Design, Fabrication and Characterization
|
| Presentation Title |
Understanding grain refinement and gas bubble evolution in U-10Mo fuel using phase-field modeling |
| Author(s) |
Sourabh Bhagwan Kadambi, Larry K Aagesen, Benjamin Beeler |
| On-Site Speaker (Planned) |
Sourabh Bhagwan Kadambi |
| Abstract Scope |
Monolithic U-10Mo fuel undergoes significant microstructural changes in the form of grain refinement and gas bubble formation during burnup, which degrades its mechanical properties. In this talk, I present a phase-field model for microstructure evolution in U-10Mo developed using the Multiphysics Object-Oriented Simulation Environment (MOOSE) framework. Simulations demonstrate that grain refinement initiates at pre-existing grain boundaries (GBs) to eliminate the lattice distortion energy caused by the accumulation of self-interstitial loops. By employing an equation of state for xenon gas, we simulate the evolution of gas bubbles in the polycrystal microstructure. Large, interconnected bubbles are found to form along the triple junctions. The effects of defect production rate, diffusivities and GB mobility on the microstructure evolution are systematically studied. Homogenization is employed on the microstructures to obtain effective elastic constants and diffusivity as a function of fission density. The simulations provide critical insights on microstructure and property degradation in U-10Mo fuel. |