Instrument Description
The metallic fuel line is housed in the Experimental Fuels Facility, Fuel Manufacturing Facility, and the Fuels and Applied Science Building. Metallic nuclear fuels have been a leading candidate for advanced transmutation, and high-flux test reactor fuel forms. These fuels have the advantage of ease of fabrication (as compared to many ceramic fabrication processes) and high thermal conductivity as well as a large fuel behavior data based on the operation of the Experimental Breeder Reactor-II reactor. The Materials and Fuels Complex (MFC), as part of INL, has all the capabilities and expertise needed to fabricate the individual fuel forms, characterize the fuel, and assemble the fuel samples into an irradiation test.
Applications
The MFC has metal fuel fabrication capabilities for both transuranic and nontransuranic fuel compositions. These capabilities start with the ability to handle fuel alloys in an inert (<10 ppm oxygen) environment, protecting the fuel from further oxidation (if needed) and the worker and surrounding environment from contamination concerns. Metal casting capabilities range from a few grams to a few kilograms, with flexible systems that can be modified to cast a number of required shapes. If the desired shape cannot be obtained directly from casting, machining capabilities for the uranium alloys also exist including a CNC lathe, mill, centerless grinder, gun drill, and electrodischarge machining center. In addition to casting, MFC has the capability to extrude, draw or roll canned uranium alloys or bare uranium alloys. After the fuel form is produced, if needed, heat treatments can be performed in a number of furnaces. Heat treatments can include annealing in either inert or vacuum atmospheres, as well as water quenching. After the fuel is fabricated, the samples can be encapsulated or double encapsulated in cladding in preparation for irradiation testing. The final encapsulation is performed through automated gas tungsten arc welding, or roll bonding in the case of aluminum clad plate type fuel. Throughout the entire metal fuel fabrication process, quality assurance/control processes are in place to dimensionally and microstructurally characterize the fuel alloy as well as the final encapsulated samples that are ready for insertion into a test reactor. Microstructural characterization can be done using standard thermomechanical characterization equipment as well as optical and electron microscopy. Reactor insertion is the final goal of many of the MFC fabrication processes, and therefore adequate quality assurance programs are in place to ensure tests can be inserted in the desired reactor.