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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 631 records · Page 35
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Development of a new casting method to fabricate U–Zr alloy containing minor actinides

Metal fuel slugs of U–Zr alloys for a sodium-cooled fast reactor (SFR) have conventionally been fabricated using an injection casting method. However, casting alloys containing volatile radioactive constituents, such as Am, are problematic in a conventional injection casting method. As an alternative fabrication method, low pressure gravity casting has been developed. Casting soundness, microstructural characteristics, alloying composition, density, and fuel losses were evaluated for the following as-cast fuel slugs: U–10 wt% Zr, U–10 wt% Zr–5 wt% RE, and U–10 wt% Zr–5 wt% RE–5 wt% Mn. The U and Zr contents were uniform throughout the matrix, and impurities such as oxyen, carbon, and nitrogen satisfied the specification of total impurities less than 2,000 ppm. The appearance of the fuel slugs was generally sound, and the internal integrity was shown to be satisfactory based on gamma-ray radiography. In a volatile surrogate casting test, the U–Zr–RE–Mn fuel slug showed that nearly all of the manganese was retained when casting was done under an inert atmosphere.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2019

The Need for Minor Actinide Production

The US Department of Energy (DOE) manages an inventory of materials that contains a range of long-lived radioactive isotopes that were produced from the 1960s through the 1980s by irradiating targets in production reactors to produce special heavy isotopes for DOE programmatic use, scientific research, and industrial and medical applications. Oak Ridge National Laboratory (ORNL) used many of these materials as feedstock in the calutron Electromagnetic Isotope Enrichment Facility (EIEF), one of only two facilities in the world with capabilities to enrich radioisotopes in multigram quantities. Both the production reactors and enrichment facilities have been shut down, and many of these unique materials will never be produced again. ORNL maintains a major portion of the United States’ inventory of these materials and uses them in DOE’s center for production, storage, and distribution of transuranium isotopes (plutonium through californium) to the user community. The US inventory of enriched actinides is being depleted, and attempts for over a decade to obtain critical supplies from foreign sources have been unsuccessful. Significant strides have been made recently in the development of new and improved enrichment technologies to replace the previous electromagnetic separations techniques. This paper summarizes the US’s need for production of high-purity enriched actinides by national security, nuclear nonproliferation, and basic research programs.

Robinson, Sharon↗