金属熔体黏度与结构相关性的分子动力学模拟

运用EAM(embed atom method)作用势，采用非平衡分子动力学模拟获得Al熔体的偶分布函数与黏度数值随温度的变化曲线，偶分布函数的计算结果与实验值符合得较好.对模拟所得到的黏度数据编程实现黏度的Arrhenius公式拟合，得到激活能E.并利用模拟所得到的黏度值及激活能对Lennard-Jones(L-J)作用势进行修正，获得黏度与偶分布函数及原子间相互作用势之间的关系式，两条黏度拟合曲线与分子动力模拟结果符合得比较好，说明拟合程序的编写是比较成功的，实现了对L-J作用势的修正.该研究为金属及合金原子间相互作用势的建立提供了新的思路. 关键词： 非平衡分子动力学模拟 L-J作用势修正 Al熔体 结构与黏度相关性

Molecular dynamics simulation of the correlation between the viscosity and structure of liquid metal

The non-equilibrium molecular dynamics simulation (NEMD) has been performed based on the embeded atom potential to obtain the pair correlation function and the viscosity of liquid Al.The pair correlation function by the simulation agrees well with Waseda's X\|ray diffraction measurement.The temperature dependence of viscosity meets the Arrhenius formula:η=Aexp(E/RT) and the activation energy E calculated is 15968.27J/mol.The expression between the viscosity, pair correlation function and the inter-atomic potential has been obtained by application of the simulated viscosity value and the activation energy to meet L-J potential.The two fitted curves of viscosity agree well with that obtained by the NEMD method,showing the fitting program we compiled is excellent and the fitting to the L-J potential is achieved.This present work provides a new method to explore inter-atomic potential.