Pulsed Neutron Characterization of Irradiated Fuels at LANSCE

Dr. Sven Vogel — Technical Staff Member at Los Alamos National Laboratory

Abstract: Neutrons offer bulk, non-destructive characterization of irradiated materials for which other bulk methods, e.g., X-ray tomography, are not suitable due to the immense gamma background emitted from the samples. In particular, pulsed neutrons provide information from the ability to resolve the neutron energy using their time-of-flight. This enables the potential to utilize neutron absorption resonance to characterize the spatial distribution of isotopes. As was demonstrated previously [1-5], neutron resonance spectroscopy may allow to characterize the distribution of fission and neutron capture products non-destructively. Besides neutron resonance-based radiography and tomography, neutron diffraction provides information on the microstructure (texture, crystallographic phases and their phase fractions). Both of these techniques may ultimately be applied to the bulk of an irradiation capsule prior to destructive post-irradiation examination to identify regions of interest. Characterization of the entire irradiated sample volume with these techniques will ultimately identify normal and abnormal regions within the entire irradiated volume, guiding destructive evaluation and thus maximizing insight from expensive irradiation campaigns. As a step towards this goal, an Advanced Test Reactor irradiated U-10Zr-1Pd sample was characterized with an NSUF funded rapid turnaround experiment (RTE). U-10Zr metallic fuels are researched as host materials for potential transmutation fuels and the addition of palladium strives to bind lanthanides, thus preventing fuelcladding chemical interactions (FCCI). This is the first pulsed neutron characterization of an irradiated fuel at LANSCE.

Biography: Sven Vogel received a Ph.D. (Dr. rer. nat.) in Physics in 2000 from Christian-Albrecht University, Kiel, Germany, and holds diplomas (equivalent to U.S. master degree) in physics and mineralogy from the same university. In 2001 he came to Los Alamos National Laboratory as a postdoc in the Materials Science and Technology Division and became staff in 2002 at the Los Alamos Neutron Science Center (LANSCE). His research interests include deformation mechanisms and phase transformations in metals, alloys, and rocks; in-situ neutron and synchrotron diffraction loading measurements; texture measurements; phase transformation textures; Bragg-edge and resonance absorption neutron transmission and imaging; radiography & tomography. He has operated the neutron diffractometer HIPPO at LANSCE since 2002, with over 400 user proposals carried out. He received the Award of Excellence for a significant contribution to the stockpile stewardship in 2005 and 2009 and the LANSCE User Facility Director's Award 2009. He is also Faculty Adjunct at New Mexico Institute of Mining and Technology (2011-present). Sven has authored and co-authored over 400 publications with over 10,000 citations per Google Scholar and contributed to chapters for several textbooks.