b' A series of commissioning tests were The first MiniFuel irradiation in Highfabrication of oxide dispersion completed in Transient Reactor TestFlux Isotope Reactor of both coatedstrengthened (ODS) steels by Facility using the Separate Effects Testand uncoated nitride microspheresextrusion/pilgering continued.Holder (SETH) irradiation capsule,was completed and postirradiation Postirradiation examinations (PIE) demonstrating the function of allexamination was initiated.Visualwere completed on X501, an full-size critical systems. These were the firstexams, gamma-spectroscopy, andU-20Pu-10Zr metallic fuel pin transient fuel tests conducted infission gas release data has beenwith Np and Am additions that was the U.S. in ~30 years and representobtained.This capsule-based, separateirradiated in Experimental Breeder a significant leap forward ineffects approach to fuel testingReactor (EBR)-II to 6% burnup; this experimental technology. promises to provide fundamental dataPIE data will be used in additionalThe development and deployment ofthat will be valuable to advanced fuelassessments of similar metallic fuels the Minimal Activation Retrievablemodeling efforts.Uranium silicideirradiated in cadmium-shrouded Capsule Holder (MARCH) sub- (U 3 Si 2 ) specimens were fabricatedpositions in the ATR.module was used to conduct theat Los Alamos National Laboratory The first thermal property first fueled Replace with Reactivity- (LANL) and shipped to Oak Ridgemeasurements on U-10Zr metallic Initiated Accident (RIA) experimentsNational Laboratory (ORNL) for afuels irradiated to over 10% burnup in TREAT in a water environment,subsequent MimiFuel irradiation inin Fast Flux Test Facility (FFTF) were and the first RIA experiments wereHFIR next year. obtained in the new Thermophysical performed on an unirradiated ATF Machining capabilities for trans- Properties Cell at the Irradiated concept (U 3 Si 2 ). uranic-bearing metallic fuels wereMaterials Characterization LaboratoryAn Advanced Reactor Fuel Workshopdeveloped and deployed in the Fuelat Idaho National Laboratory (INL).was co-hosted with Gateway forManufacturing Facility in order to The AFC-4C (Alternative Metallic Accelerated Innovation in Nucleardemonstrate many of the innovativeFuel Alloys Experiment) and AFC-3F (GAIN) at Boise State University indesign features developed in recent(Metallic Fuels Fabrication Variables March 2019.Industry advancedyears, including sodium-free U-Pu-ZrExperiment) continued irradiation in reactor designers briefed themetallic fuels as an advanced drivercadmium-shrouded positions in ATR campaign on their fuel conceptsfuel for the VTR. The first two annularthroughout FY19; both experiments and research needs, which will bemetallic fuel slugs of U-20Pu-10Zrare nearing their 10% burnup targets.incorporated into campaign R&Dwere produced.The Integrated Recycle Test (IRT) plans for the future.Extensive characterization studiescontaining metallic fuels fabricatedConceptual design of the newwere conducted on metallic fuelsremotely using actinide materials Fission Accelerated Steady-state Testwith additives (Pd, Sn) for lanthaniderecovered from spent fuel continued (FAST) irradiation experiment wasfission product immobilization,irradiation in cadmium-shrouded completed, which will use miniatur- which are showing great promisepositions in the ATR throughout ized fuel rods to accelerate burnuptoward increasing the allowableFY19, which will provide important accumulation by as much as a factorcladding temperatures in metallic fuelinformation on the performance of 10, greatly reducing the timepins.A major update to the Metallicof recycled metallic fuels; peak fuel required for reactor testing. Fuels Handbook was issued, incorpo- burnup was nearing 3% at year end. FAST fabrication trials on miniaturerating a considerable amount of new Considerable enhancements to the fuel rodlets were successfullydata generated by the campaign. BISON fuel performance code were completed this year, including rodlets Good progress was made on themade for simulations of metallic with integral Zr, V liners; the firstprocessing and characterization fuels, including the addition of a new FAST experiments with metallic fuelof nano-structured ferritic alloys,mechanistic fuel swelling model, rodlets are scheduled for insertionwith a view to developing a newwhich was used to investigate the in ATR during the 168A cyclecladding for sodium fast reactorsdeformation behavior of Na-free, (December 2019). capable of higher temperature slotted metallic fuel concepts.operation, and experimental 2019|AFC ACCOMPLISHMENTS 13'