Simulation of Dendrite Morphology and Micro-Segregation in U-Nb Alloy During Solidification

Due to the importance of uranium and uranium alloys to national defence and nuclear industrial applications, it is necessary to understand dendrite formation in their solidification structures and to control their microstructures. In this study, a modified cellular automaton model was developed to predict 2-D and 3-D equiaxed dendrite growth in U-Nb alloys. The model takes into account solute diffusion, preferential growth orientation, interface curvature, etc., and the solid fraction increment is calculated using the local level rule method. Using this model, 2-D large-scale and 3-D equiaxed dendrite growth with various crystallographic orientations in the U-5.5Nb alloy were simulated, and the Nb micro-segregation behaviour during solidification was analysed. The simulated results showed reasonable agreement with the as-cast microstructure observed experimentally.

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1. This work was supported by the Major Project of China Academy of Engineering Physics under grant No. TA1401, the Science Challenge Program of China under Grant No. TZ20160040201, the National Natural Science Foundation of China under Grant No. 51904276, and the Program for Science and Technology Innovation Talents in Universities of Henan Province under Grant No. 22HASTIT031.

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2. Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2022-2023).