Effects of impurities and stacking fault energy on shock-induced phase changes in copper alloys

ORAL

Abstract

Recent publications suggest a relationship between stacking fault (SF) generation and the face-centered cubic (FCC) to body-centered cubic (BCC) phase transformation in shock-compressed noble metals. Metal alloying is well known to affect many material properties including stacking fault energy (SFE) and phase stability regions. To examine the effect of impurities on stacking fault generation and high-pressure phase boundaries, we performed laser-shock in-situ X-ray diffraction (XRD) experiments on three copper alloys with SFEs between 10 and 90 mJ/m2. For the different Cu alloys (≥70% Cu), we found FCC to BCC transition stresses between ~130 and ~280 GPa, highlighting the large effect impurities can have on transition stress. Due to the observed linear relationship between SFE and FCC to BCC transition stress, for small impurity contents, we expect minimal phase boundary changes.

*This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. (LLNL-ABS-844850)

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Presenters

  • Travis J Volz

    • Lawrence Livermore Natl Lab

Authors

  • Travis J Volz

    • Lawrence Livermore Natl Lab

  • Chris McGuire

    • Lawrence Livermore Natl Lab

  • Cara Vennari

    • Lawrence Livermore Natl Lab

  • Raymond F Smith

    • Lawrence Livermore Natl Lab

  • Melissa Sims

    • Johns Hopkins University

  • June K Wicks

    • Johns Hopkins University

  • Sally J Tracy

    • Carnegie Institution for Science

  • Samantha M Clarke

    • Lawrence Livermore Natl Lab

  • Richard Briggs

    • Lawrence Livermore Natl Lab
    • Lawrence Livermore National Laboratory

  • Jon H Eggert

    • Lawrence Livermore Natl Lab
    • LLNL
    • Lawrence Livermore National Lab

  • A. Krygier

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab