b'a state-of-the-art R&D infrastruc- for such activities is secured.In Fabrication and assembly of the ture necessary to accelerate theaddition, a number of Strategic Leadsfirst MiniFuel capsules containing development of new fuel con- were established to take a longer viewmonolithic specimens of UO 2and cepts; and on fuels R&D needs of the futureU 3 Si 2fuels was completed and began 5.collaborate with NEAMS on theand identity those fuel technologiesirradiation in HFIR Cycle 487, with development and validation ofmost appropriate for maturation totarget burnup levels of 8-10 and multi-scale, multi-physics, andthe point where they might become28-40 GWD/MTU.increasingly predictive fuel per- formal qualification programs.Those The activity to install an I-Loop in formance models and codes. interested in learning more about theATR for prototypic ramp and run-to-new structure will find it presented infailure testing of PWR and BWR fuel Two developments of special notethe FY20 update to the AFC Programrods became a formal project, and during FY20 were the following. Execution Plan. fabrication began on a new Top Head First, with the Congressional appro- This report provides concise summa- Closure Plate to be installed during priation bill passed in Decemberries of many of the significant AFCthe Core Internals Changeout (CIC) 2019, funding for the R&D activitiesaccomplishments made during FY20. in FY21.This new testing capability associated with advanced reactor fuelOf particular note are the followingis needed to support qualification of development was essentially elimi- key accomplishments and theirboth ATF and high burnup fuels for nated.Some accomplishments hadsignificance: commercial reactors.already been achieved during the first Grain growth kinetic modelsquarter of the fiscal year, and some ATF-2 completed 244 EFPDs ofwere developed for undoped UO 2in funding was provided for an orderlyirradiation in the ATR pressurizedorder to provide grain sizes similar close out major activities in progress. water loop with Westinghouse,to those in doped UO 2fuels, which However, the portion of the Accom- Framatome, and General Electricwill be used in synthesizing mate-plishments Report dedicated to thetest rods. Three new twelve-inch- rials to be used as reference stan-Advanced Reactor Fuel Developmentlong test rods were fabricated fordards for fission gas release studies.Focus Area is considerably smallerWestinghouse and installed in a A biaxial flexure strength test was this year for that reason.Second,newly designed tier. The new tierdeveloped and qualified for use the structure of the campaign wasincreases the number of rods thaton UO 2and other nuclear fuels to significantly reorganized in order tocan be irradiated. aid in understanding cracking and create better alignment with the new After ~184 effective full-power daysattempts to mitigate it, especially in funding realities and shifting R&Dof irradiation, ATF-2 was reconfig- high burnup fuels.Future work will priorities.There are now Qualificationured to ATF-2B1 and reinstalled intoemploy this system to characterize Leads in the areas of both Accidentthe Advanced Test Reactor 2A Loopdoped UO 2 .Tolerant Fuels and High Burnup Fuelsto resume irradiation. The ATF-2B1 to guide near-term activities, interactconfiguration included new BWR-A revision of the Handbook on more directly with industry FOAtype ATF rodlets supplied by GE inthe Material Properties of FeCrAl teams, and coordinate with importantTiers 3 and 4. The PWR-type rodletsAlloys was issued, with a significant stakeholders (e.g., EPRI, NRC).It isin Tiers 1, 2, and 5 are now oper- focus on updating the experimental hoped that such Qualification Leadsating at more prototypical pressuredatabase to include the alloy C26M, can be established for advanced fuelsand temperature. a leading ATF alloy deployed in lead product lines in the future, as fundingtest rods in commercial reactors.2020|AFC ACCOMPLISHMENTS 11'