NSUF 18-1178: In situ study of “rim effect” microstructure modification of nuclear fuels (resubmitted)
[With the positive reviewers' comments from previous RTE call, this proposal is resubmitted with a slight modification on sample preparation to match facility capability]
From an atomic-scale perspective, there are still many open questions concerning the mechanisms driving the high burn-up structure formation and its evolution during continued irradiation. Thus, the real time observation of defect evolution using IVEM-Tandem facility, can be beneficial to record the atomistic processes that are associated with dislocation/stacking fault formation. Under Kr irradiation, study of the ion-solid interaction and energy deposition at elevated temperature will provide insights for defect formation and help in the prediction of fuel material modification during reactor operation. Combining microstructural and microanalytical experimental studies using state of the art characterization tools, such as high resolution TEM, bright/dark field image and selected area electron diffraction. These atom-scale approach will provide greatly improved insight into the fundamental physical processes controlling the problematic rim effect microstructure evolution in nuclear fuels. In the proposed experiments, defects and microstructural behavior under extreme irradiation conditions will be compared among different fluorite oxide materials (UO2 and CeO2, along with comparisons with previous work on Gd2O3 and Lu2O3). Revealing the defect formation process in UO2 at the atomic scale will be beneficial for understanding the early stage of the complex high burn-up damage accumulation process. The behavior of irradiation-induced point defects and their accumulation into planar defects can provide a bridge between atomic structure evolution and later resulting microstructural changes. In addition, the ability to control the formation of dislocations at different temperatures by ion irradiation can provide insight into the irradiation stability of nano-structured advanced nuclear fuels. We anticipate observing the formation of dislocation networks and stacking faults under irradiation. A long turn defect incubation process may also be observed due to the competition between the formation of dislocation and point defect annihilation between the dislocation structure.
Additional Info
| Field | Value |
|---|---|
| Abstract | [With the positive reviewers' comments from previous RTE call, this proposal is resubmitted with a slight modification on sample preparation to match facility capability] From an atomic-scale perspective, there are still many open questions concerning the mechanisms driving the high burn-up structure formation and its evolution during continued irradiation. Thus, the real time observation of defect evolution using IVEM-Tandem facility, can be beneficial to record the atomistic processes that are associated with dislocation/stacking fault formation. Under Kr irradiation, study of the ion-solid interaction and energy deposition at elevated temperature will provide insights for defect formation and help in the prediction of fuel material modification during reactor operation. Combining microstructural and microanalytical experimental studies using state of the art characterization tools, such as high resolution TEM, bright/dark field image and selected area electron diffraction. These atom-scale approach will provide greatly improved insight into the fundamental physical processes controlling the problematic rim effect microstructure evolution in nuclear fuels. In the proposed experiments, defects and microstructural behavior under extreme irradiation conditions will be compared among different fluorite oxide materials (UO2 and CeO2, along with comparisons with previous work on Gd2O3 and Lu2O3). Revealing the defect formation process in UO2 at the atomic scale will be beneficial for understanding the early stage of the complex high burn-up damage accumulation process. The behavior of irradiation-induced point defects and their accumulation into planar defects can provide a bridge between atomic structure evolution and later resulting microstructural changes. In addition, the ability to control the formation of dislocations at different temperatures by ion irradiation can provide insight into the irradiation stability of nano-structured advanced nuclear fuels. We anticipate observing the formation of dislocation networks and stacking faults under irradiation. A long turn defect incubation process may also be observed due to the competition between the formation of dislocation and point defect annihilation between the dislocation structure. |
| Award Announced Date | 2018-02-01T14:13:17.213 |
| Awarded Institution | Center for Advanced Energy Studies |
| Facility | Microscopy and Characterization Suite |
| Facility Tech Lead | Wei-Ying Chen, Yaqiao Wu |
| Irradiation Facility | None |
| PI | Rodney Ewing |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 1178 |