Effects of hot extrusion and heat treatment on microstructure characteristics of uranium-2.1%molybdenum alloy

doi:10.13251/j.issn.0254-6051.2024.06.030

Abstract

Abstract: The phase structure, composition and microstructure characteristics of uranium-molybdenum alloy with 2.1%Mo under different processing conditions such as hot extrusion, diffusion annealing, quenching and tempering were studied by using microstructure analysis techniques. The results show that the microstructure of the alloy varies greatly under different hot working processes. The hot extrusion process has little effect on the alloy phase composition but leads to obvious changes on the phase structure and microstructure characteristics, resulting in increased hardness and strength of the alloy. The quenching process causes significant changes in the alloy phase composition, structure and microstructure, transforming it into an α′_b single-phase martensitic structure close to that of the α phase, which significantly increases the alloy hardness and strength but reduces its plasticity and toughness. The diffusion annealing and tempering processes eliminate the effects of stress and strain or rapid phase transformations on the phase structure, phase composition and microstructure characteristics, restoring the relevant microstructure characteristics to a state of uniform annealing, and improving the plasticity and toughness of the alloy.

Key words: uranium-molybdenum alloy, hot extrusion, heat treatment, microstructure, phase composition, phase structure

CLC Number:

TL48

Du Jijun, Guo Hong, Xu Yong, He Jinming, Li Bo, Yang Ruonan. Effects of hot extrusion and heat treatment on microstructure characteristics of uranium-2.1%molybdenum alloy[J]. Heat Treatment of Metals, 2024, 49(6): 183-189.

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