Phase transformation of metastable discontinuous precipitation products to equilibrium phases in U10Mo alloys

SCRIPTA MATERIALIA

卷:156

Article

Devaraj, Arun¹  Kautz, Elizabeth¹  Kovarik, Libor²  Jana, Saumyadeep³  Overman, Nicole³  Lavender, Curt³  Joshi, Vineet V.³ 

[1] Pacific Northwest Natl Lab, Phys & Computat Sci Directorate, POB 999, Richland, WA 99354 USA

[2] Pacific Northwest Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99354 USA

[3] Pacific Northwest Natl Lab, Energy & Environm Directorate, POB 999, Richland, WA 99354 USA

关键词: Phase transformation;    Discontinuous precipitation;    Microstructural evolution;    Characterization;   

DOI  :  10.1016/j.scriptamat.2018.07.010

来源: Elsevier

【 摘 要 】

The discontinuous precipitation (DP) mechanism is prevalent in over 80 alloy systems. We report a new type of DP occurring along prior gamma-UMo grain boundaries of an alloy of uranium with 10 wt% molybdenum (U10Mo) during annealing at 500 degrees C, forming alternate lamellae of Mo-enriched gamma-UMo and alpha-U. During prolonged annealing, the metastable Mo-enriched gamma-UMo lamellae gradually transform into a composite mixture of equilibrium gamma'-U2Mo embedded in Mo-depleted gamma-UMo. Using high resolution scanning transmission electron microscopy and atom probe tomography, a comprehensive description of the structural and compositional changes of the metastable lamellar DP product to near-equilibrium phases is provided. (C) 2018 Published by Elsevier Ltd on behalf of Acta Materialia Inc.

【 授权许可】

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