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DOI	10.1073/pnas.2017809118
	Metastable-solid phase diagrams derived from polymorphic solidification kinetics
	Sadigh B.; Zepeda-Ruiz L.; Belof J.L.
发表日期	2021
ISSN	00278424
卷号	118 期号:9
英文摘要	Nonequilibrium processes during solidification can lead to kinetic stabilization of metastable crystal phases. A general framework for predicting the solidification conditions that lead to metastable-phase growth is developed and applied to a model face-centered cubic (fcc) metal that undergoes phase transitions to the body-centered cubic (bcc) as well as the hexagonal close-packed phases at high temperatures and pressures. Large-scale molecular dynamics simulations of ultrarapid freezing show that bcc nucleates and grows well outside of the region of its thermodynamic stability. An extensive study of crystal-liquid equilibria confirms that at any given pressure, there is a multitude of metastable solid phases that can coexist with the liquid phase. We define for every crystal phase, a solid cluster in liquid (SCL) basin, which contains all solid clusters of that phase coexisting with the liquid. A rigorous methodology is developed that allows for practical calculations of nucleation rates into arbitrary SCL basins from the undercooled melt. It is demonstrated that at large undercoolings, phase selections made during the nucleation stage can be undone by kinetic instabilities amid the growth stage. On these bases, a solidification-kinetic phase diagram is drawn for the model fcc system that delimits the conditions for macroscopic grains of metastable bcc phase to grow from the melt. We conclude with a study of unconventional interfacial kinetics at special interfaces, which can bring about heterogeneous multiphase crystal growth. A first-order interfacial phase transformation accompanied by a growth-mode transition is examined. © This open access article is distributed under Creative Commons Attribution-NonCommercialNoDerivatives License 4.0 (CC BY-NC-ND).
英文关键词	Kinetic stabilization; Metastability; Phase diagram; Phase transitions; Solidification
语种	英语
scopus关键词	article; calculation; crystallization; grain; growth curve; phase transition; solid
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180468
作者单位	Lawrence Livermore National Laboratory, Physical and Life Sciences Directorate, Livermore, CA 94550, United States
推荐引用方式 GB/T 7714	Sadigh B.,Zepeda-Ruiz L.,Belof J.L.. Metastable-solid phase diagrams derived from polymorphic solidification kinetics[J],2021,118(9).
APA	Sadigh B.,Zepeda-Ruiz L.,&Belof J.L..(2021).Metastable-solid phase diagrams derived from polymorphic solidification kinetics.Proceedings of the National Academy of Sciences of the United States of America,118(9).
MLA	Sadigh B.,et al."Metastable-solid phase diagrams derived from polymorphic solidification kinetics".Proceedings of the National Academy of Sciences of the United States of America 118.9(2021).