Density-functional study of the U-Zr system

JOURNAL OF ALLOYS AND COMPOUNDS

卷:478

Article

Landa, Alex¹  Soederlind, Per¹  Turchi, Patrice E. A.¹ 

[1] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA

关键词: Nuclear reactor materials;    Phase transitions;    Computer simulations;   

DOI  :  10.1016/j.jallcom.2008.12.052

来源: Elsevier

【 摘 要 】

Density-functional formalism is applied to study the phase equilibria in the U-Zr system The obtained. ground-state properties of the gamma (bcc) and delta (C32) phases are in good agreement with experimental data. The decomposition curve for the gamma-based U-Zr solutions is calculated. Our calculations confirm that experimentally observed partial ordering of the alloy components in the delta-UZr2 (AlB2) phase, in which Zr atoms occupy the Al position and the two B sites are randomly shared by the U and Zr atoms, is the most energetically favorable within the C32 structure. We argue that stabilization of the delta-UZr2 phase relative to the alpha-Zr (hcp) structure is due to an increase of the Zr d-band occupancy that occurs when U is alloyed with Zr. A comparison with stabilization of the omega-phase (also C32) in Zr under compression is made. (C) 2008 Elsevier B.V. All rights reserved.

【 授权许可】

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