摘要
界面能密度是表征纳米复合材料与结构界面力学性质的重要物理量.采用分子动力学方法计算了不同面心立方金属晶体构成的双材料纳米薄板结构的界面能密度,分析了界面晶格结构形貌变化及界面效应对原子势能的影响.结果表明:双材料纳米薄板界面具有周期性褶皱状疏密相间的晶格结构形貌,界面上原子势能亦呈现周期性分布特性,而靠近界面的两侧原子势能与板内原子势能具有明显差异.拉格朗日界面能密度和欧拉界面能密度均随双层薄板厚度的增加而增加,最终趋向于块体双材料结构的界面能密度.
The interface free energy density is an important quantity characterizing the mechanical property of interface in nanocomposite systems. In this paper, molecular dynamics simulation method is adopted to investigate the interface energy density of different FCC metallic bi-nano-scaled plates. The morphology of the interface crystal structure and the interface effect on the atomic potential are analyzed. It is found that interface atoms have periodically wrinkled rarefied or serried configurations, and the potential energy of interface atoms is also periodically distributed. The potential energy of atoms near the interface is obviously different from that of atoms inside the nano-plates. Both the Lagrange interface energy and the Eulerian one increase with the increase of the thickness of the bi-material, which approach the interface energy of a bulk bi-material finally.
引文
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