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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Kenneth M. Wasywich, William H. Hocking, David W. Shoesmith, Peter Taylor
Nuclear Technology | Volume 104 | Number 3 | December 1993 | Pages 309-329
Technical Paper | Special Issue on Waste Management / Radioactive Waste Management | doi.org/10.13182/NT93-A34893
Articles are hosted by Taylor and Francis Online.
In the Canadian research and development program on fuel storage, used CANDU (Canada deuterium uranium) UO2fuel bundles are being exposed in experimental vessels to both dry and moisture-saturated air environments at 150°C. At intervals of several years, individual fuel elements, which were deliberately defected before storage, are recovered for destructive examination to determine the extent of UO2 oxidation that has occurred. The most recent examinations took place after 99.5 and 69 months of storage under dry and moist conditions, respectively. The progress of oxidation in the two different storage environments is compared, and the results of fuel examination by optical microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRD) are described. In dry air, oxidation proceeds mainly on exposed UO2 surfaces near the cladding defect and penetrates the fuel along grain boundaries adjoining cracks and the fuel-sheath gap, which provide primary pathways for access of oxygen to the fuel. An oxidized rind, resembling α-U3O7, is visible around UO2 grain cores near the oxide front. In moist air, oxidation is more generally distributed throughout the length of the fuel element. It proceeds along grain boundaries and is most extensive in regions of the fuel expected to have the highest porosity or grain-boundary inventory of fission products. This oxidized layer is too thin to observe by optical microscopy or identify by XRD, but XPS results indicate a higher degree of oxidation at the exposed grain boundaries (U6+/U4+ often »1.0) than in fuel specimens oxidized in dry air (U6+/U4+ usually <1.0). Interpretation of the results is complicated by the different O2/UO2 ratios in the two types of storage vessel and the fact that oxygen was completely consumed during at least some of the storage intervals. Nonetheless, it is clear that the presence of moisture promotes a more generally distributed oxidation of UO2 grain boundaries. The probable involvement of radiolytic processes in the moist oxidation reaction and possible reasons for the sensitization of certain regions of the fuel to moist oxidation are discussed. In addition to oxidation of UO2, the XPS spectra provide evidence for the radiation-induced incorporation of oxygen and nitrogen into adventitious carbon (adsorbed hydrocarbons) on the UO2 surfaces.
