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Title: Atomistic simulations of thermodynamic properties of Xe gas bubbles in U10Mo fuels

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Journal Article: Publisher's Accepted Manuscript
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Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 490; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-04 15:29:44; Journal ID: ISSN 0022-3115
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Hu, Shenyang, Setyawan, Wahyu, Joshi, Vineet V., and Lavender, Curt A. Atomistic simulations of thermodynamic properties of Xe gas bubbles in U10Mo fuels. Netherlands: N. p., 2017. Web. doi:10.1016/j.jnucmat.2017.04.016.
Hu, Shenyang, Setyawan, Wahyu, Joshi, Vineet V., & Lavender, Curt A. Atomistic simulations of thermodynamic properties of Xe gas bubbles in U10Mo fuels. Netherlands. doi:10.1016/j.jnucmat.2017.04.016.
Hu, Shenyang, Setyawan, Wahyu, Joshi, Vineet V., and Lavender, Curt A. 2017. "Atomistic simulations of thermodynamic properties of Xe gas bubbles in U10Mo fuels". Netherlands. doi:10.1016/j.jnucmat.2017.04.016.
title = {Atomistic simulations of thermodynamic properties of Xe gas bubbles in U10Mo fuels},
author = {Hu, Shenyang and Setyawan, Wahyu and Joshi, Vineet V. and Lavender, Curt A.},
abstractNote = {},
doi = {10.1016/j.jnucmat.2017.04.016},
journal = {Journal of Nuclear Materials},
number = C,
volume = 490,
place = {Netherlands},
year = 2017,
month = 7

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on April 18, 2018
Publisher's Accepted Manuscript

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  • Xe gas bubble superlattice formation is observed in irradiated uranium–10 wt% molybdenum (U10Mo) fuels. However, the thermodynamic properties of the bubbles (the relationship among bubble size, equilibrium Xe concentration, and bubble pressure) and the mechanisms of bubble growth and superlattice formation are not well known. In this work, molecular dynamics is used to study these properties and mechanisms. The results provide important inputs for quantitative mesoscale models of gas bubble evolution and fuel performance. In the molecular dynamics simulations, the embedded-atom method (EAM) potential of U10Mo-Xe (Smirnova et al. 2013) is employed. Initial gas bubbles with low Xe concentration aremore » generated in a U10Mo single crystal. Then Xe atom atoms are continuously added into the bubbles, and the evolution of pressure and dislocation emission around the bubbles is analyzed. The relationship between pressure, equilibrium Xe concentration, and radius of the bubbles is established. It was found that the gas bubble growth is accompanied by partial dislocation emission, which results in a star-shaped dislocation structure and an anisotropic stress field. The emitted partial dislocations have a Burgers vector along the <111> direction and a slip plane of (11-2). Dislocation loop punch-out was not observed. A tensile stress was found along <110> directions around the bubble, favoring the nucleation and formation of a face-centered cubic bubble superlattice in body-centered cubic U10Mo fuels.« less
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