title: Asymmetric crystallization during cooling and heating in model glass-forming systems.
abstract: We perform molecular dynamics (MD) simulations of the crystallization process in binary Lennard-Jones systems during heating and cooling to investigate atomic-scale crystallization kinetics in glass-forming materials. For the cooling protocol, we prepared equilibrated liquids above the liquidus temperature Tl and cooled each sample to zero temperature at rate Rc. For the heating protocol, we first cooled equilibrated liquids to zero temperature at rate Rp and then heated the samples to temperature T>Tl at rate Rh. We measured the critical heating and cooling rates Rh* and Rc*, below which the systems begin to form a substantial fraction of crystalline clusters during the heating and cooling protocols. We show that Rh*>Rc* and that the asymmetry ratio Rh*/Rc* includes an intrinsic contribution that increases with the glass-forming ability (GFA) of the system and a preparation-rate dependent contribution that increases strongly as Rp→Rc* from above. We also show that the predictions from classical nucleation theory (CNT) can qualitatively describe the dependence of the asymmetry ratio on the GFA and preparation rate Rp from the MD simulations and results for the asymmetry ratio measured in Zr- and Au-based bulk metallic glasses (BMG). This work emphasizes the need for and benefits of an improved understanding of crystallization processes in BMGs and other glass-forming systems.
authors: Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA.|Center for Research on Interface Structures and Phenomena, Yale University, New Haven, Connecticut 06520, USA.
authors: Minglei
authors: M
authors: Wang
authors: Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA.|Center for Research on Interface Structures and Phenomena, Yale University, New Haven, Connecticut 06520, USA.
authors: Kai
authors: K
authors: Zhang
authors: Department of Physics and Benjamin Levich Institute, The City College of the City University of New York, New York, New York 10031, USA.
authors: Zhusong
authors: Z
authors: Li
authors: Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA.|Center for Research on Interface Structures and Phenomena, Yale University, New Haven, Connecticut 06520, USA.
authors: Yanhui
authors: Y
authors: Liu
authors: Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA.|Center for Research on Interface Structures and Phenomena, Yale University, New Haven, Connecticut 06520, USA.
authors: Jan
authors: J
authors: Schroers
authors: Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA.|Department of Physics and Benjamin Levich Institute, The City College of the City University of New York, New York, New York 10031, USA.
authors: Mark D
authors: MD
authors: Shattuck
authors: Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA.|Center for Research on Interface Structures and Phenomena, Yale University, New Haven, Connecticut 06520, USA.|Department of Physics, Yale University, New Haven, Connecticut 06520, USA.|Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
authors: Corey S
authors: CS
authors: O'Hern