Technetium-99m is a diagnostic radio-pharmaceutical that is currently used in 85% of the United States diagnostic imaging procedures [1]. All supplies of technetium-99m's parent isotope molybdenum-99 currently originate from the irradiation of high enriched uranium (HEU) in nuclear reactor facilities located outside the United States. In accordance with the Global Threat Reduction Initiative all uranium used in future molybdenum-99 production will use low enriched uranium (LEU). Conversion to LEU material effectively mandates using LEU in the form of a metal foil as opposed to current powder based dispersion designs for HEU. Using a foil requires a significant modification to the current target design. One design approach uses an LEU foil sandwiched between two nominally flat aluminum plates. The LEU is enclosed in the sandwiched structure by welding the aluminum plates together about their edges. The plate design is inspired by LEU fuel plates with the exception that the LEU is not bonded to the aluminum plates nor is it necessary to clamp the plate edges to prevent lateral translation. This paper will review the thermal-mechanical analysis of an LEU based molybdenum-99 target with plate geometry. This study describes the impact of boundary conditions on the thermally-induced stress and strain in the aluminum plates.
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