Observation of Compression-Induced Phase Transformations in Zirconium using Ultrafast X-Ray Diffraction

ORAL

Abstract

The mechanisms of phase transitions in bulk materials are analogous to the transition state in the study of chemical reactions. Detailed knowledge of these mechanisms (and the ability to control them) has the potential to revolutionize material synthesis. Studying such phenomena is difficult, however, since the fundamental mechanisms of phase transitions occur on near-atomic (nm) length scales at the speed of sound (1-10 nm/ps for condensed phases), implying picosecond time scales. Using 130 fs x-rays at the LCLS-MEC beamline, we interrogated phase transformation pathways of Zr at the spatial and temporal scales of these fundamental mechanisms. Zr was dynamically compressed to pressures up to 130 GPa, driven by ~120 picosecond duration laser pulses with energies in the range of 2.5-250 mJ. We observed an intermediate body-centered cubic (bcc) β-Zr phase on the transformation path from the hexagonal close-packed (hcp) α-Zr phase towards the P6/mmm ω-Zr phase under rapid compression. At 33 GPa compression, we observed the initial α-Zr phase transform into the β-Zr phase, bypassing the lower-pressure ω-Zr phase. At 130 GPa, we observed direct melting of Zr from the α phase, followed by recrystallization on a longer ns timescale.

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Prepared by LLNL under Contract DE-AC52-07NA27344

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Presenters

  • Harry Radousky

    • Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

Authors

  • Harry Radousky

    • Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Michael Armstrong

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab
    • Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory

  • Jon Belof

    • Lawrence Livermore National Laboratory
    • Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Ryan Austin

    • Lawrence Livermore Natl Lab

  • Elissaios Stavrou

    • Lawrence Livermore National Laboratory
    • Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Shaughnessy Brown

    • Mechanical Engineering, Stanford University
    • SLAC

  • Jonathan Crowhurst

    • Lawrence Livermore Natl Lab

  • Arianna Gleason

    • Los Alamos National Laboratory
    • LANL

  • Eduardo Granados

    • SLAC National Accelerator Laboratory
    • SLAC

  • Paulius Grivickas

    • Lawrence Livermore Natl Lab

  • Nicholas Holtgrewe

    • Geophysical Laboratory, Carnegie Institution of Washington

  • Haeja Lee

    • SLAC National Accelerator Laboratory
    • SLAC

  • Tian Li

    • Lawrence Livermore Natl Lab

  • Sergey Lobanov

    • Geophysical Laboratory, Carnegie Institution of Washington

  • Joseph McKeown

    • Lawrence Livermore Natl Lab

  • Robert Nagler

    • SLAC National Accelerator Laboratory
    • SLAC

  • Inhyuk Nam

    • SLAC

  • Art Nelson

    • Lawrence Livermore National Lab
    • Lawrence Livermore Natl Lab

  • Vitali Prakapenka

    • University of Chicago, Center for Advanced Radiation Sources
    • ANL

  • Clemens Prescher

    • University of Cologne

  • John Roehling

    • Lawrence Livermore Natl Lab

  • Nick Teslich

    • Lawrence Livermore Natl Lab

  • Peter Walter

    • SLAC

  • Joseph Zaug

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Alexander Goncharov

    • Geophysical Laboratory, Carnegie Institution of Washington