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DOE OSTI · 3001433

Evaluation of U10Mo Fuel Plate Performance Modeling Over Hot Isostatic Press and Hydraulic Bending for MURR DDE Plates

Abstract

The United States High Performance Research Reactor Program’s objective is to reduce the amount of highly enriched uranium currently implemented in research reactors. The conversion of these research reactors requires designing a monolithic U10Mo plate fuel, with the fuel plate geometry being dependent on each research reactor. The process of forming the plates includes a hot isostatic pressing (HIP) to manufacture a prototypic plate. In the case of the Missouri University Research Reactor (MURR) design demonstration element (DDE) plate manufacture, plates that have been through HIP are then curved using dies and a hydraulic press to impart the desired curvature. Both fabrication processes impart residual stresses into each fuel plate region, with the curvature of the plates taking some regions of the fuel plate up to their material yield stresses, accompanied by plastic strain. The amount of plastic strain and stress imparted onto each MURR DDE plate is determined by the radius of curvature, thickness of each region, and overall width of the fuel plates. Furthermore, this work aims to predict the yield stresses and strain using ABAQUS to simulate the proposed fabrication process of the MURR DDE plates, accompanied by discussion over the stresses and strains as to their relation to nuclear fuel performance and the impact they will have during early irradiation.

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Paaren, Kyle Mitchell [Idaho National Laboratory (INL), Idaho Falls, ID (United States)], Schulthess, Jason L. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000242897528), Barney, Jason Wayne [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0009000070803210), Ozaltun, Hakan [US Nuclear Regulatory Commission (NRC), Rockville, MD (United States)]. 2025-09-23. Evaluation of U10Mo Fuel Plate Performance Modeling Over Hot Isostatic Press and Hydraulic Bending for MURR DDE Plates. https://doi.org/10.1080/00295639.2025.2545155

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