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

• 成果类型: Article
• 署名作者: Belof, Jonathan L.; Brown, Justin L.; Myint, Philip C.; Sterbentz, Dane M.; Hao, Yue; Stoltzfus, Brian S.; Benedict, Lorin X.
• 署名单位: United States Department of Energy (DOE); Lawrence Livermore National Laboratory; United States Department of Energy (DOE); Sandia National Laboratories
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-11958
• DOI: 10.1073/pnas.2424703122
• 发表日期: 2025-05-20
• 关键词: kinetics; water; simulations

摘要

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 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 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.