About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
|
Accelerated Qualification of Nuclear Materials Integrating Experiments, Modeling, and Theories
|
Presentation Title |
The Role of Grain Boundaries in Irradiation Enhanced Creep: A Cluster Dynamics Study of UO2 |
Author(s) |
William D. Neilson, Conor O.T. Galvin, Michael W.D. Cooper, David A Andersson |
On-Site Speaker (Planned) |
William D. Neilson |
Abstract Scope |
Creep is a highly studied process in UO2 fuel; an enhanced creep rate is observed under irradiation, but the mechanism and the role of the grain boundary (GB) is not fully understood. Fuel performance codes designed to aid accelerated fuel qualification aim to capture creep behavior; insight on the creep mechanism is needed to enhance the model and to predict how creep may be impacted in alternate fuel forms. A new cluster dynamics model has been built to predict defect concentrations at UO2 GBs under irradiation. The model predicts that at temperatures where irradiation enhanced creep has been observed, the concentration of U interstitials at the GB is raised by orders of magnitude, compared the grain interior. We show that—owing to these interstitials—irradiation enhanced creep in UO2 involves defect diffusion occurring at the GB: i.e., Coble creep. |
Proceedings Inclusion? |
Planned: |