NSUF 13-412: STEM/LEAP Study of Fission Product Transportation in Neutron Irradiated TRISO Fuel Particles
The objective of the proposed project is to build a complete understanding of the active fission product (FP) release mechanisms from intact TRISO fuel, with a primary focus on the release of Ag, by determining the distribution of FPs in the silicon carbide (SiC) layer of irradiated TRISO fuel. TRISO fuel is the fuel of choice of the Very High Temperature Gas Reactor concept and is composed of a spherical UO2/UC fuel kernel, carbon buffer layer, and successive isotropic layers of inner pyrolytic carbon, SiC, and outer pyrolytic carbon. During operation the SiC layer serves as the main metallic fission product (FP) barrier, however during operation multiple FP have been observed to be released from intact fuel. Release of FPs limits the fuel operating lifetime, reducing the reactor economics and creates significant safety and maintenance concerns. To date little direct evidence on the responsible mechanisms for release of specific FPs have been identified. Confirming the active release mechanisms is the first step to development of engineering solutions to mitigate release, ultimately improving reactor economics and safety. This work builds off of previous work from the collaborators from the University of Wisconsin-Madison (UW) and Idaho National Laboratory (INL). The work at UW has focused on computational experiments and simulated Ag diffusion experiments and observed grain boundary (GB) fast diffusion and precipitate transport to be active transport mechanisms. The initial advanced microscopy conducted by the INL collaborators at the Electron Microscopy Laboratory (EML) at the Materials and Fuels complex (MFC) at INL has indicated similar active transport mechanisms in real irradiated fuel from the AGR-1 irradiation campaign at INL, but have not been able to identify Ag in the system due to characterization technique limitations. The proposed work will utilize the advanced analytical capabilities housed at CAES to investigate the composition of FP precipitates and the composition of FPs segregated to GBs in the SiC layer of irradiated TRISO fuel from the AGR-1 irradiation campaign. Specifically, scanning transmission electron microscopy with electron energy loss spectroscopy (STEM-EELS) and local electrode atom probe (LEAP) will be employed. STEM-EELS will be utilized to investigate multiple features of interests providing an overview of the FP distribution throughout the SiC layer, while LEAP will be employed to gain insight on fine scale features such as precipitates < 2nm in diameter and GB concentrations where the GB width is < 0.5 nm. Insight on the chemistry of FP features decorating the SiC layer will provide insight on which mechanisms are responsible for the release of specific FPs from intact fuel. This will ultimately support the development of TRISO fuel for the advanced gas reactor fuel qualification and development project and provide direct evidence of the release mechanisms.
Tilleggsinformasjon
| Felt | Verdi |
|---|---|
| Awarded Institution | University of Wisconsin |
| Embargo End Date | 2026-02-27 |
| Facility Tech Lead | Alina Montrose, Mukesh Bachhav |
| NSUF Call | FY 2013 RTE Solicitation |
| PI | Izabela Szlufarska |
| Project Member | Dr. Tyler Gerczak - Oak Ridge National Laboratory (https://orcid.org/0000-0001-9967-3579) |
| Project Member | Dr. Isabella van Rooyen, Senior Technical Advisor Advanced Material Systems - Pacific Northwest National Laboratory (https://orcid.org/0000-0001-8524-938X) |
| Project Member | bin leng - University of Wisconsin |
| Project Member | Izabela Szlufarska - University of Wisconsin |
| Project Type | RTE |
| Publication | Effect of carbon ion irradiation on Ag diffusion in SiC Tyler Gerczak, bin leng, Kumar Sridharan, Izabela Szlufarska Journal of Nuclear Materials 471 2017-04-17 http://www.sciencedirect.com/science/article/pii/S0022311515303251#ack0010 |
| Publication | Methods for identification of crystallographic parameters of irradiated SiC to understand fission product transport The 3rd Workshop on HTGR SiC Material Properties 2014-09-30 - 2014-10-01 |
| Publication | Methods for identification of crystallographic parameters of irradiated SiC to understand fission product transport The 3rd Workshop on HTGR SiC Material Properties 2014-09-30 - 2014-10-01 |
| Publication | Methods for identification of crystallographic parameters of irradiated SiC to understand fission product transport The 3rd Workshop on HTGR SiC Material Properties 2014-09-30 - 2014-10-01 |
| Publication | Development and Application of Advanced Characterization Techniques to understand Irradiated TRISO Fuel Behavior The 3rd Workshop on HTGR SiC Material Properties 2014-09-30 - 2014-10-01 |
| Publication | Approach and Micro-analysis techniques applied to study fission product transport mechanisms in neutron irradiated SiC layers IMRC XXIII 2014-08-17 - 2014-08-21 |
| Publication | Identification of Ag-phase in TRISO fuels by Atom Probe Tomography Materials Science & Technology 2016-10-23 - 2016-10-27 |
| Publication | Microstructure Characterization of TRISO fuels by Atom Probe Tomography TMS2016, 145th Annual Meeting & Exhibition 2016-02-14 - 2016-02-18 |
| Publication | Microstructure Characterization of TRISO fuels by Atom Probe Tomography TMS2016, 145th Annual Meeting & Exhibition 2016-02-14 - 2016-02-18 |
| Publication | Microstructure Characterization of TRISO fuels by Atom Probe Tomography TMS2016, 145th Annual Meeting & Exhibition 2016-02-14 - 2016-02-18 |
| Publication | Correlation of fission product transport to grain boundary character in neutron irradiated tristructural isotropic coated nuclear fuel particles TMS2016, 145th Annual Meeting & Exhibition 2016-02-14 - 2016-02-18 |
| Publication | Effect of Sample Preparation Techniques on Grain Boundary Characterization of Annealed TRISO-Coated Particles Mary Lou Dunzik-Gougar, Isabella van Rooyen Nuclear Technology 196(1) 2016-10-31 https://www.researchgate.net/publication/308766634_Sample_Preparation_Techniques_for_Grain_Boundary_Characterization_of_Annealed_TRISO-Coated_Particles |
| Publication | Electron Microscopy Study of Pd, Ag, and Cs in Carbon Areas in the Locally Corroded SiC Layer in a Neutron-Irradiated TRISO Fuel Particle Haiming Wen, Isabella van Rooyen, John Hunn, Tyler Gerczak Journal of the European Ceramic Society 38 (2018) 2016-10-31 https://www.sciencedirect.com/science/article/abs/pii/S0955221918302991 |
| Publication | Influence of SiC grain boundary character on fission product transport in irradiated TRISO fuel Journal of Nuclear Materials 473 https://www.sciencedirect.com/science/article/abs/pii/S0022311516300381 |
| Publication | Influence of SiC grain boundary character on fission product transport in irradiated TRISO fuel Journal of Nuclear Materials 473 2016-01-01 https://www.sciencedirect.com/science/article/abs/pii/S0022311516300381 |
| Publication | Observations of Ag diffusion in ion implanted SiC Tyler Gerczak, bin leng, Kumar Sridharan Journal of Nuclear Materials 461 2015-06-01 https://www.sciencedirect.com/science/article/abs/pii/S0022311515001749 |
| Publication | Precession electron diffraction for SiC grain boundary characterization in unirradiated TRISO fuel Nuclear Engineering and Design 305 2016-08-15 https://www.sciencedirect.com/science/article/abs/pii/S002954931630142X |
| Publication | STEM/EDS Analysis of Fission Products in Irradiated TRISO Coated Particles of the AGR-1 Experiment Journal of Nuclear Materials 475 https://www.sciencedirect.com/science/article/abs/pii/S0022311516300812 |
| Publication | STEM/EDS Analysis of Fission Products in Irradiated TRISO Coated Particles of the AGR-1 Experiment Journal of Nuclear Materials 475 https://www.sciencedirect.com/science/article/abs/pii/S0022311516300812 |
| Publication | STEM/EDS Analysis of Fission Products in Irradiated TRISO Coated Particles of the AGR-1 Experiment Journal of Nuclear Materials 475 https://www.sciencedirect.com/science/article/abs/pii/S0022311516300812 |
| Publication | STEM/EDS Analysis of Fission Products in Irradiated TRISO Coated Particles of the AGR-1 Experiment Journal of Nuclear Materials 475 (2016) https://www.sciencedirect.com/science/article/abs/pii/S0022311516300812 |
| Publication | The Effect of High Temperature Annealing on the Grain Characteristics of a Thin Chemical Vapor Deposition Silicon Carbide Layer Microscopy and Microanalysis 19 (Suppl. 2) https://www.researchgate.net/publication/309295742_The_Effect_of_High_Temperature_Annealing_on_the_Grain_Characteristics_of_a_Thin_Chemical_Vapor_Deposition_Silicon_Carbide_Layer |
| Publication | Distribution of fission products palladium, silver, cerium and cesium in the un-corroded areas of the locally corroded SiC layer of a neutron irradiated TRISO fuel particle Haiming Wen, Isabella van Rooyen Journal of the European Ceramic Society 37 (2017) 2017-04-28 https://www.sciencedirect.com/science/article/abs/pii/S0955221917302455 |
| RTE Number | 412 |