Measuring twinning and slip in shock-compressed Ta from in-situ x-ray diffraction

ORAL

Abstract

A fundamental understanding of high-pressure and high-strain-rate deformation rests on grasping the underlying microstructural processes, such as twinning and dislocation generation and transport (slip), yet simulations and \textit{ex-post-facto} recovery experiments provide conflicting answers to these basic issues. Here, we report direct, in-situ observation of twinning and slip in shock compressed Ta using in-situ x-ray diffraction. A series of shock experiments were performed on the Matter in Extreme Conditions end station at LCLS. Direct laser ablation was used to drive a shock, ranging in pressure from 10-300 GPa, into a Ta sample with an initial (110) fiber texture. The subsequent changes in texture were observed in-situ by examining the azimuthal distribution of the diffraction intensity and found to match twinning and lattice rotation. Measurements of the twin fraction and lattice rotation were used to calculate the equivalent plastic strain from twinning and slip.

*This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344.

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Authors

  • Christopher Wehrenberg

    • Lawrence Livermore Natl Lab
    • Lawrence Livermore National Laboratory

  • David McGonegle

    • University of Oxford

  • Marcin Sliwa

    • University of Oxford, UK
    • University of Oxford

  • Matt Suggit

    • University of Oxford

  • Justin Wark

    • University of Oxford

  • Hae Ja Lee

    • SLAC National Accelerator Laboratory
    • Matter in Extreme Conditions Instrument
    • SLAC
    • Stanford Linear Accelerator

  • Bob Nagler

    • SLAC National Accelerator Laboratory
    • SLAC
    • Stanford Linear Accelerator

  • Franz Tavella

    • Stanford Linear Accelerator

  • Bruce Remington

    • Lawrence Livermore Natl Lab
    • Lawrence Livermore National Laboratory

  • Rob Rudd

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Amy Jenei

    • Lawrence Livermore National Laboratory

  • Hye-Sook Park

    • Lawrence Livermore Natl Lab
    • Lawrence Livermore National Laboratory

  • Damian Swift

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Louis Zepeda-Ruiz

    • Lawrence Livermore National Laboratory

  • Andrew Higginbotham

    • University of York
    • University of York, UK

  • Cynthia Bolme

    • Los Alamos Natl Lab
    • Los Alamos National Laboratory
    • LANL