Interpreting dynamic-compression experiments to uncover the time dependence of freezing: Application to gallium

Journal Article · Wed May 14 00:00:00 UTC 2025 · Proceedings of the National Academy of Sciences of the United States of America

DOI: https://doi.org/10.1073/pnas.2424703122 · OSTI ID:2566322

Belof, Jonathan L.  ^[1]; Brown, Justin L. ^[2]; Myint, Philip C.  ^[1]; Sterbentz, Dane M. ^[1]; Hao, Yue ^[1]; Stoltzfus, Brian S.  ^[2]; Benedict, Lorin X.  ^[1]

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1. Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
2. Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

Using pulsed-power magnetic field sources to compress gallium to gigapascal pressures on nanosecond timescales, we report here experiments on shockless dynamic compression of a liquid metal. Time-resolved velocimetry data reveal signatures of rapid freezing from a metastable liquid state, and we demonstrate that the kinetics of this nonequilibrium solidification can be accurately simulated with a computational modeling framework we have developed in previous studies, where classical nucleation theory is coupled with hydrodynamics. Notably, velocity traces in some of our experiments show evidence of a phase transition, while others do not, even though other types of evidence suggest that solidification may be occurring in all of them. We explain how predictions made by our models regarding the presence or absence of these phase-transition signatures motivated additional experiments that later confirmed the theoretical predictions. Our analysis shows that due to the rapid, quasi-isentropic nature of the loading path, our experiments were able to compress liquid gallium to metastable states that are undercooled below the equilibrium melt temperature by more than 300 K and exhibit pressures that approach five times the equilibrium melt pressure. The understanding gained in this study should form the basis for future dynamic-compression experiments aimed at interrogating melt curves at high pressures.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE; USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC52-07NA27344; NA0003525
• OSTI ID: 2566322
• Report Number(s): LLNL--JRNL-2003765
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 20 Vol. 122; ISSN 1091-6490; ISSN 0027-8424
• Publisher: National Academy of SciencesCopyright Statement
• Country of Publication: United States
• Language: English