Materials in Nuclear Energy Systems (MiNES) 2021: Fuels and Actinide Materials- Fabrication Methodology
Program Organizers: Todd Allen, University of Michigan; Clarissa Yablinsky, Los Alamos National Laboratory; Anne Campbell, Oak Ridge National Laboratory
Tuesday 10:30 AM
November 9, 2021
Room: Urban
Location: Omni William Penn Hotel
Session Chair: David Andersson, Los Alamos National Laboratory
10:30 AM Invited
Advanced Technology Fuel Accelerated Development at Bangor University: Simon Middleburgh1; Phylis Makrurunje1; Fabio Martini1; Mustafa Bolukbasi1; Michael Rushton1; William Lee2; 1Bangor University; 2Bangor University; Imperial College London
Bangor University’s Nuclear Futures Institute was initiated in 2017 to grow expertise and train new scientists and engineers in the North Wales region of the UK. Developing new technologies for the nuclear fuel cycle has played a central role in the group, linking to our strong international collaborators within universities, national laboratories, and industry. Advanced technology fuels (ATFs) are being developed simultaneously using experimental efforts and through modelling methods, accelerating our understanding towards a commercially viable concept. The focus of this presentation will be to highlight the advances made in several kernel fuel and composite fuel concepts that incorporate higher uranium densities (e.g. with the inclusion of UN), burnable absorbers (for example ZrB2), high thermal conductivity or a combination thereof. The experimental techniques applied have an eye to industrial scalability, and the modelling techniques consider not only the materials aspects but also the fuel cycle economics.
11:10 AM
Synthesis of UN-U3Si2 Composite Fuels by Spark Plasma Sintering and Properties Characterization: Bowen Gong1; Erofili Kardoulaki2; Andre Broussard1; Dong Zhao1; Joshua White2; Kathryn Metzger3; Michael Sivack3; Kenneth Mcclellan2; Edward Lahoda3; Jie Lian1; 1Rensselaer Polytechnic Institute; 2Los Alamos National Laboratory; 3Westinghouse Electric Company
UN-U3Si2 composites are considered as a potential candidate of accident tolerant fuels because of their high uranium density and thermal conductivity. However, the UN-U3Si2 composite experiences thermal mismatch-induced micro-cracking in the fuel pellets sintered by conventional approaches. Here, we explore the feasibility of using spark plasma sintering (SPS) to synthesize UN-U3Si2 composites with different fractions of silicides (25 ~ 75 wt%). The phase and microstructure of the UN-U3Si2 composites are characterized, and micro-cracking can be mitigated by controlling sintering conditions. Thermal-mechanical properties and oxidation resistance of the composite fuels are characterized by laser flash, indentation and dynamic oxidation tests. An UN-50 wt% U3Si2 composite displays simultaneously-high strength and fracture toughness and excellent thermal conductivity. The onset temperatures of the composites are close to 530 °C, suggesting an improved oxidation resistance than monolithic UN. These results highlight the potential of synergizing UN and U3Si2 in composites with enhanced properties.
11:30 AM
Fabrication of Potentially High Burnup Annular U-10Zr Fuel by SPS: Dong Zhao1; Michael Benson2; Fidelma Lemma2; Jie Lian1; 1Rensselaer Polytechnic Institute; 2Idaho National Laboratory
Contrasting with a solid fuel design, the annular metallic fuel (U-10Zr, wt%) shows ultra-high burnup potential, better fuel-cladding chemical interaction performance, and no need for sodium bonding. During irradiation of U-10Zr, an interconnected porosity allows fission gas to escape to the plenum. Here, annular U-10Zr fuel pellets with controlled porosity and pore structure was fabricated by spark-plasma-sintering (SPS) with a special graphite die design. To mimic the irradiated structure for metallic fuel, pressure-less die design and sacrificed pore formers were used to fabricate the bi-model pore structure fuel, which has interconnected large-sized (20~30 μm) pores embedded with micron-sized fine pores. The homogenous microstructure is achieved by controlling the current flow during the sintering process. The results not only show the capabilities of SPS for advanced fuel fabrication, but can also be used to investigate the properties of irradiated metallic fuel structure with a thermal gradient, simulating the nuclear reactor environment.