2017 | AFC ACCOMPLISHMENTS 100 2.5 IRRADIATIONTESTING AND PIETECHNIQUES ATF-1 Postirradiation Examination Highlights for 2017 Principal Investigator: Jason M. Harp Collaborators: Luca Capriotti, Areva, Westinghouse Postirradiation examination (PIE)of the AdvancedTest Reactor (ATR) irradiated AccidentTolerant Fuel (ATF) concepts continues at the Idaho National Laboratory (INL) Hot Fuel Examina- tion Facility (HFEF).This year the first destructive tests were performed on ATF-1 concepts, and the first examina- tions were performed on uranium silicide (U3Si2) irradiated at prototypic light water reactor conditions. Project Description: These irradiations are designed to provide data on several different potential ATF concepts.The ATF-1 irradiations are drop-in style tests that test a fuel cladding and fuel meat Figure 1. Optical Microscopy cross section from ATF-1A R1 (UO­2-Zircaloy-4).