Phase Stability in U-6Nb Alloy Doped with Ti from the First Principles Theory

Landa, Alexander; Söderlind, Per; Wu, Amanda

doi:10.3390/app10103417

Title: Phase Stability in U-6Nb Alloy Doped with Ti from the First Principles Theory

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Abstract

First-principles calculations within the density-functional-theory (DFT) approach are conducted in order to explore and explain the effect of small amounts of titanium on phase stability in the U-6Nb alloy. During rapid quenching from high to room temperature, metastable phases α' (orthorhombic), α" (monoclinic), and γ⁰ (tetragonal) can form, depending on Nb concentration. Important mechanical properties depend on the crystal structure and, therefore, an understanding of the effect of impurities on phase stability is essential. Insights on this issue are obtained from quantum-mechanical DFT calculations. The DFT framework does not rely on any material-specific assumptions and is therefore ideal for an unbiased investigation of the U-Nb system.

Authors:

Landa, Alexander ^[1]; Söderlind, Per ^[1]; Wu, Amanda ^[1]

Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: Fri May 15 00:00:00 EDT 2020

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1762877

Report Number(s):: LLNL-JRNL-807617
Journal ID: ISSN 2076-3417; 1013264

Grant/Contract Number:: AC52-07NA27344

Resource Type:: Accepted Manuscript

Journal Name:: Applied Sciences

Additional Journal Information:: Journal Volume: 10; Journal Issue: 10; Journal ID: ISSN 2076-3417

Publisher:: MDPI

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; density-functional theory; uranium-niobium alloys; metastable phase; metallic fuels; thermodynamic modeling

Citation Formats


                    Landa, Alexander, Söderlind, Per, and Wu, Amanda. Phase Stability in U-6Nb Alloy Doped with Ti from the First Principles Theory.  United States: N. p., 2020. 
Web.  doi:10.3390/app10103417.

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                    Landa, Alexander, Söderlind, Per, & Wu, Amanda. Phase Stability in U-6Nb Alloy Doped with Ti from the First Principles Theory.  United States.  https://doi.org/10.3390/app10103417

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                    Landa, Alexander, Söderlind, Per, and Wu, Amanda. Fri .  
"Phase Stability in U-6Nb Alloy Doped with Ti from the First Principles Theory".  United States.  https://doi.org/10.3390/app10103417.  https://www.osti.gov/servlets/purl/1762877.

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@article{osti_1762877,

  title        = {Phase Stability in U-6Nb Alloy Doped with Ti from the First Principles Theory},

  author       = {Landa, Alexander and Söderlind, Per and Wu, Amanda},

  abstractNote = {First-principles calculations within the density-functional-theory (DFT) approach are conducted in order to explore and explain the effect of small amounts of titanium on phase stability in the U-6Nb alloy. During rapid quenching from high to room temperature, metastable phases α' (orthorhombic), α" (monoclinic), and γ0 (tetragonal) can form, depending on Nb concentration. Important mechanical properties depend on the crystal structure and, therefore, an understanding of the effect of impurities on phase stability is essential. Insights on this issue are obtained from quantum-mechanical DFT calculations. The DFT framework does not rely on any material-specific assumptions and is therefore ideal for an unbiased investigation of the U-Nb system.},

  doi          = {10.3390/app10103417},

  journal      = {Applied Sciences},

  number       = 10,

  volume       = 10,

  place        = {United States},

  year         = {Fri May 15 00:00:00 EDT 2020},

  month        = {Fri May 15 00:00:00 EDT 2020}

}

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