NSUF 22-4461: In situ irradiation of fission nanoprecipitates
Nuclear fuel undergoes significant microstructural and chemical evolution during reactor operations. Some fission products are retained within the UO2 matrix in solid solution, while the inert gases, xenon (Xe) and krypton (Kr) and the 4d group metals, molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), and palladium (Pd) are trapped as bubbles and metallic precipitates, respectively in the UO2 matrix. We recently found the metallic nanoprecipitates and fission gas nanoprecipitates form pair-structure or not form pair-structure at rim area of a nuclear fuel but the mechanism of pairing or unpairing has not been revealed. To predict potential release in the event of cladding failure during loss-of-coolant accident (LOCA) or spent nuclear fuel (SNF) storage, transportation, or long-term geological disposal, it is important to know the distribution and evolution of these fission nanoprecipitates in nuclear fuels. An innovative approach is to use ion irradiation at various temperatures to trigger the microstructure change of fission nanoprecipitates in a nuclear fuel. Implantations of Xe ions will be performed to mimic fission products generation during reactor operation. The decoupling of inert gas nanoprecipitates and metal nanoprecipitates under thermal annealing and under annealing/irradiation at various temperatures will be visualized using in situ transmission electron microscopy (TEM). Besides nanoprecipitates evolution introduced by Xe ion irradiation, the dynamic process of nucleation and growth of dislocation loops/lines will also be captured to reveal the radiation damage. This rapid turnaround project includes 1-week TEM sample preparation using FEI Quanta 3D focused ion beam system (FIB) at the Irradiated Materials Characterization Laboratory (IMCL) facility, Idaho National Laboratory, 1-week in situ TEM observation using IVEM-Tandem facility at Argonne National Laboratory, experimental data analysis and final report, which will take about 9 months in total.
Additional Info
| Field | Value |
|---|---|
| Abstract | Nuclear fuel undergoes significant microstructural and chemical evolution during reactor operations. Some fission products are retained within the UO2 matrix in solid solution, while the inert gases, xenon (Xe) and krypton (Kr) and the 4d group metals, molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), and palladium (Pd) are trapped as bubbles and metallic precipitates, respectively in the UO2 matrix. We recently found the metallic nanoprecipitates and fission gas nanoprecipitates form pair-structure or not form pair-structure at rim area of a nuclear fuel but the mechanism of pairing or unpairing has not been revealed. To predict potential release in the event of cladding failure during loss-of-coolant accident (LOCA) or spent nuclear fuel (SNF) storage, transportation, or long-term geological disposal, it is important to know the distribution and evolution of these fission nanoprecipitates in nuclear fuels. An innovative approach is to use ion irradiation at various temperatures to trigger the microstructure change of fission nanoprecipitates in a nuclear fuel. Implantations of Xe ions will be performed to mimic fission products generation during reactor operation. The decoupling of inert gas nanoprecipitates and metal nanoprecipitates under thermal annealing and under annealing/irradiation at various temperatures will be visualized using in situ transmission electron microscopy (TEM). Besides nanoprecipitates evolution introduced by Xe ion irradiation, the dynamic process of nucleation and growth of dislocation loops/lines will also be captured to reveal the radiation damage. This rapid turnaround project includes 1-week TEM sample preparation using FEI Quanta 3D focused ion beam system (FIB) at the Irradiated Materials Characterization Laboratory (IMCL) facility, Idaho National Laboratory, 1-week in situ TEM observation using IVEM-Tandem facility at Argonne National Laboratory, experimental data analysis and final report, which will take about 9 months in total. |
| Award Announced Date | 2022-06-14T07:26:53.943 |
| Awarded Institution | Idaho National Laboratory |
| Facility | Advanced Test Reactor |
| Facility Tech Lead | Alina Zackrone, Wei-Ying Chen |
| Irradiation Facility | Intermediate Voltage Electron Microscopy (IVEM)-Tandem Facility |
| PI | Lingfeng He |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 4461 |