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用quantum Sutton-Chen 多体势对Ag6Cu4和CuNi液态金属凝固过程进行了分子动力学模拟研究, 在冷却速率为2 1012 K/s时, 通过键型分析, 证实CuNi形成fcc晶体结构, 而Ag6Cu4则形成了非晶态结构. 其原因在于AgCu中原子半径之比(为1.130)较CuNi中原子半径之比(为1.025)大, 显示出原子的尺寸差别的确是非晶态合金形成的一个主要影响因素. 而对AgxCu1-x在冷却速率为2 1012 K/s凝固过程的模拟, 发现对应于二元相图深共晶成分处, 最容易得到非晶态合金, 证实了合金化效应对非晶态合金的形成倾向和稳定性的关键作用. 此外,采用键型指数法和原子成团类型指数法对微观结构组态变化的分析, 不仅能说明二十面体结构在非晶态合金形成和稳定性中所起的关键作用, 且有助于对液态金属的凝固过程、非晶态结构特征的进一步理解.
Molecular dynamics simulations were performed on the solidification process of Ag6Cu4 and CuNi liquid metals by the quantum Sutton-Chen multi-body potential. The bond-type analysis confirmed that CuNi forms fcc crystal structure at a cooling rate of 2 1012 K / s, whereas Ag6Cu4 The reason for this is that the ratio of the atomic radii in AgCu (1.130) to the atomic radii in CuNi (1.025) is large, indicating that the size difference of the atoms is indeed a major factor in the formation of the amorphous alloy The simulation of the solidification process of AgxCu1-x at a cooling rate of 2 1012 K / s shows that the amorphous alloy is most easily obtained corresponding to the deep eutectic composition of the binary phase diagram, confirming the effect of the alloying effect on the amorphous state Alloy formation tendency and stability of the key role.In addition, the use of bond index method and atomic agglomeration type index method of microstructure changes in the structure analysis, not only can explain the icosahedral structure in amorphous alloy formation and stability In the role of the key, and help to liquid metal solidification process, the amorphous structure of the further understanding.