Glass-forming ability of elemental zirconium

Article

关键词: INITIO MOLECULAR-DYNAMICS;    EMBEDDED-ATOM POTENTIALS;    CRYSTAL NUCLEATION;    LIQUID;    SIMULATION;    SOLIDIFICATION;    TRANSITION;    METALS;    HCP;    CRYSTALLIZATION;   

DOI  :  10.1103/PhysRevB.102.104205

来源: SCIE

【 摘 要 】

We report large-scale molecular dynamics simulations of the glass formation from the liquid phase and homogeneous nucleation phenomena of pure zirconium. For this purpose, we have built a modified embedded atom model potential in order to reproduce relevant structural, dynamic, and thermodynamic properties from ab initio and experimental data near the melting point. By means of liquid-solid interface simulations, we show that this potential provides a thermodynamic melting temperature and densities of the solid and liquid state in good agreement with experiments. Using melt-quenching simulations with one million atoms, we determine the glass transition from the temperature evolution of the inherent structure energy as well as the nose of the time-temperature-transformation curve located in the deep undercooling regime. We identify the local structural origin of the glass-forming ability as a competition between bcc and fivefold polytetrahedral structures that may represent an impediment of rapid homogeneous nucleation at such high undercoolings. This suggests the ability of single elemental zirconium to form a glass from the melt with cooling rates of at least 10(12) K/s, compatible with modern experiments.

【 授权许可】

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