Cao Xianying, Sun Minhua
Department of Mathematics and Physics, Harbin Institute of Petroleum, Harbin, 150000, China.
Department of Physics, Harbin Normal University, Harbin, 150025, China.
J Mol Model. 2022 Aug 20;28(9):265. doi: 10.1007/s00894-022-05269-7.
The influence of the interatomic repulsive hardness (RH) on the microstructure and dynamics of CuZr metallic glass is studied by the molecular dynamics simulation method. By constructing potential energy functions that characterize different RH, we calculated their atomic diffusion coefficients, thermal expansion coefficients, radial distribution functions, fivefold symmetry order, and other related structural properties during the quenching process. We found that the atomic diffusion coefficients and thermal expansion coefficients decrease with RH, and the variation of radial distribution functions with temperatures becomes slower in softer RH. The softening RH is also accompanied by the enhancement of the icosahedral order in the liquids. Our results explain the experimental conclusion of "soft atoms make strong glasses" when considering the relation of the repulsive potential and liquid dynamics fragility.
采用分子动力学模拟方法研究了原子间排斥硬度（RH）对CuZr金属玻璃微观结构和动力学的影响。通过构建表征不同RH的势能函数，我们计算了它们在淬火过程中的原子扩散系数、热膨胀系数、径向分布函数、五重对称序以及其他相关结构性质。我们发现，原子扩散系数和热膨胀系数随RH减小，且在较软的RH中，径向分布函数随温度的变化变得更慢。软化的RH还伴随着液体中二十面体序的增强。当考虑排斥势与液体动力学脆性的关系时，我们的结果解释了“软原子形成强玻璃”这一实验结论。
