b'2.4 LWR IRRADIATION TESTING AND PIE TECHNIQUESCharacterization of Irradiated Fuels with Pulsed Neutrons at LANSCEPrincipal Investigator: Sven C. Vogel (LANL)Team Members/ Collaborators: Alexander M. Long (LANL), D. Travis Carver (LANL), Jason Harp (ORNL), Luca Capriotti (INL),Eric J. Larson (LANL), James Angell (INL) and Aaron Craft (INL)C haracterization of irradi- of fuels is mature and sophisticated ated fuels is typically donebut measurements in hot cells are destructively to obtain samplesexpensive and typically examine small with manageable radioactivity.volumes of irradiated fuels relying on Pulsed neutrons in combination witha limited amount of knowledge of the appropriate shielding casks allowbulk characteristics of the specimen to characterization of entire irradiationselect the volume examined destruc-capsules by diffraction, energy- tively. This leaves the possibility that resolved neutron imaging and neutronkey failure inducing phenomena will absorption resonance spectroscopy. Innot be observed because of limited fiscal year (FY) 20 our team consistingPIE. For these reasons, there is value of researchers from Los Alamosin techniques that can quickly and National Laboratory (LANL), Idahonon-destructively characterize proper-National Laboratory (INL), and Oakties over volumes consistent with Ridge National Laboratory (ORNL)standard fuel geometries. Applying made progress in technique develop- such methods pre- and post irradia-ment towards designing a shieldingtion unambiguously determines the cask for neutron characterization aschanges induced by irradiation. Such well as towards characterizing a 6mmtechniques can inform models on the diameter, ~2mm thick disk of aninitial condition of samples as well irradiated U-10Zr-1Pd fuel sample. as provide the same parameters after Project Description: the irradiation. Such a technique can A key enabler for a science-basedcomplement, guide, and leverage approach for accelerated developmentdestructive post irradiation examina-and certification of new, nuclear fuels,tion by characterizing the entire such as accident tolerant fuel forms,sample. Pulsed neutron characteriza-is an early and efficient understandingtion, different from reactor-based of material behavior under irradiationneutron characterization, offers to at multiple length scales. For newfulfill this demand. For example, fuel formulations, there is a dearth ofthree dimensional characterization of irradiation testing experience. Whencomplete fuel pellets within cladding representative irradiation tests takeafter irradiation could identify regions years, it is important to extract thethat are representative of average and maximum insight possible from eachatypical response with parameters test. Post irradiation examination (PIE)not accessible by presently applied techniques such as visual inspec-78 2020|AFC ACCOMPLISHMENTS'