Dislocation Loops in Proton Irradiated Uranium-Nitrogen-Oxygen System

JOURNAL OF NUCLEAR MATERIALS

卷:557

Article

Xiu, Pengyuan^1,2  Jin, Miaomiao³  Bawane, Kaustubh¹  Tyburska-Puschel, Beata⁴  Jaques, Brian J.⁵  Field, Kevin G.²  Giglio, Jeffrey J.¹  He, Lingfeng¹ 

[1] Idaho Natl Lab, Idaho Falls, ID 83415 USA

[2] Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA

[3] Penn State Univ, Dept Nucl Engn, University Pk, PA 16802 USA

[4] Dutch Inst Fundamental Energy Res, NL-5612 AJ Eindhoven, Netherlands

[5] Boise State Univ, Micron Sch Mat Sci & Engn, Boise, ID 83725 USA

关键词: Radiation effects;    Dislocation loops;    Uranium nitride;    Nuclear fuels;   

DOI  :  10.1016/j.jnucmat.2021.153244

来源: Elsevier

【 摘 要 】

In this study, we investigated the type of dislocation loops formed in the proton-irradiated uranium-nitrogen-oxygen (U-N-O) system, which involves uranium mononitride (UN), uranium sesquinitride (alpha-U2N3), and uranium dioxide (UO2) phases. The dislocation loop formation is examined using specimens irradiated at 400 degrees C and 710 degrees C. Based on the detailed transmission-based electron microscopy characterization with i) the morphology-based on-zone and ii) the invisibility-criterion based two-beam condition imaging techniques, only a single type of dislocation loop in each phase is found: a/2 < 110 >, a/2 < 111 >, or a/3 < 111 > dislocation loops in UN, alpha-U2N3, and UO2 phases, respectively. Molecular statics calculations for the formation energy of perfect and faulted dislocation loops in the UN phase indicate a critical loop size of similar to 6 nm, above which perfect loops are thermodynamically favorable. This could explain the absence of faulted loops in the experimental observation of the irradiated UN phase at two temperatures. This work will enhance the understanding of irradiation induced microstructural evolution for uranium mononitride as an advanced nuclear fuel for the next-generation nuclear reactors. (C) 2021 Elsevier B.V. All rights reserved.

【 授权许可】

Free