High Energy X-ray Applications for the Characterization of Metallic Uranium Alloys

Journal Article · Wed Jun 15 04:00:00 EDT 2016 · Transactions of the American Nuclear Society

OSTI ID:22992157

Okuniewski, Maria A. ^[1]; Ecker, Lynne E.; Elbakhshwan, Mohamed; Sprouster, David ^[2]; Velazquez, Daniel; Seibert, Rachel L.; Lee, Daniel; Terry, Jeff H. ^[3]; Sohn, Yongho ^[4]; Miller, Brandon D.; Fielding, Randall S. ^[5]

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1. Purdue University, 701 West Stadium Ave., West Lafayette, IN 47907-2045 (United States)
2. Brookhaven National Laboratory, Upton, NY 11973-5000 (United States)
3. Illinois Institute of Technology, 3101 S. Dearborn, Chicago, IL 60616 (United States)
4. University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816-2455 (United States)
5. Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-6188 (United States)

Uranium-based metallic alloys are both candidates for fuels in high performance research and test reactors, as well as in fast spectrum reactors as nuclear transmutation fuels that can be utilized to burn long-lived minor actinides and fission products. Uranium-molybdenum (UMo) alloys are under development for the use in research and test reactors. Whereas, uranium-zirconium (U-Zr) alloys represent one of the types of fuels that are under consideration for use within the fast spectrum reactors. Both of these types of metallic fuels have been studied for over five decades in various types of reactors. Many of the previous studies had focused on performance-based aspects. However, recent advances in characterization tools and techniques, as well as short-term (low fluence) neutron irradiation facilities have contributed to a more in-depth understanding of nuclear fuel and material behavior following irradiation. This knowledge is crucial to the enhancement of current modeling and simulation techniques, particularly with respect to parameterization and validation. This paper focuses on the use of high energy x-rays to characterize metallic nuclear fuel. The specimens were composed of depleted uranium (DU) alloyed with either Zr or Mo, where DU-xZr (x = 10, 15, or 20 wt.%) and DU-yMo (y = 7 or 10 wt.%). The geometries of the specimens were 3 mm TEM disks that were ∼200 μm in thickness. The fuel alloys were initially prepared via an arc melting process. The samples were irradiated at the Advanced Test Reactor at Idaho National Laboratory (INL) using the hydraulic rabbit system. The hydraulic rabbit system allows for well-controlled, short term irradiations (less than one cycle), hence resulting in low fluences. The U-based alloys were irradiated to doses of 0.01 and 0.1 dpa. The irradiation temperature of the specimens ranged from 150 deg. C to 800 deg. C. Synchrotron characterization techniques can be used to provide insight into material microstructure ranging a multitude of spatial scales, from the atomic scale to the macroscale. High-energy x-rays at the National Synchrotron Light Source II (NSLS II) and the Advanced Photon Source (APS) have been utilized to understand the microstructural changes in these metallic alloys, specifically with respect to phase identification, phase fractions, chemical bonding, strain, and dislocation density through the use of diffraction and X-ray Absorption Spectroscopy (XAS). These experiments utilized a robot for specimen exchange during the diffraction measurements, allowing for remote handling of radioactive materials. This is an example of another recent advancement in characterization techniques that enables research with nuclear materials. Detailed results of the analyses of the microstructural changes are pending.

• OSTI ID: 22992157
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Journal Issue: 1 Vol. 114; ISSN 0003-018X
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
36 MATERIALS SCIENCE
42 ENGINEERING
ABSORPTION SPECTROSCOPY
ADVANCED PHOTON SOURCE
ATOMIC DISPLACEMENTS
DEPLETED URANIUM
DIFFRACTION
FISSION PRODUCTS
IDAHO NATIONAL LABORATORY
IRRADIATION
IRRADIATION PLANTS
MICROSTRUCTURE
NUCLEAR FUELS
SIMULATION
SYNCHROTRONS
TEST REACTORS
TRANSMISSION ELECTRON MICROSCOPY
URANIUM ALLOYS
X RADIATION
X-RAY SPECTROSCOPY