异质固-液界面自由能的计算研究

Solid-Liquid interfacial free energy plays a central role in a number of technologically important phenomena, such as heterogeneous nucleation, dendritic crystal growth, liquid-metal embrittlement and wetting. Significant progress has been realized over the past two decades in the application of molecular simulations to the studies of Solid-Liquid interfacial free energy. However, such progress is limited in the studies of the chemically homogeneous Solid-Liquid interfaces. Current proposal is aimed at carrying out pioneering computational studies on the Solid-Liquid interfacial free energy of the chemically heterogeneous interfaces. We propose to target the new developments of the methods for calculating Solid-Liquid interfacial free energy, in order to be applicable in chemically heterogeneous interfacial systems. The proposed work will also involve the systematical investigations into the relationships between the interfacial free energy and temperature, interfacial orientation and atomistic structure, for an illustrative and representative chemically heterogeneous Solid-Liquid interfacial system. The proposed research will provide essential data to facilitate the new advancements of the interfacial thermodynamics.

固-液界面自由能在一系列具有极高应用价值的重要物理现象中扮演着核心角色，如异质形核、枝晶生长、液态金属致脆和浸润等。应用分子模拟技术计算研究固-液界面自由能在过去二十年中取得了巨大进步。然而，这些进步局限于匀质固-液界面体系。本项目旨在先驱性地开展异质固-液界面体系的界面自由能计算研究工作。我们拟对固-液界面自由能的计算方法做出新的发展，以适用于异质固-液界面自由能的计算研究，并拟针对一个具有代表性的异质固-液界面体系，系统研究其界面自由能随温度、界面方向以及界面微观结构的变化规律。本项目研究的开展将为界面热力学理论新的发展提供重要数据。

固-液界面的微观结构与界面自由能等热力学量在一系列具有极高应用价值的重要物理现象中扮演着核心角色，如异质形核、枝晶生长、液态金属致脆和浸润等。应用分子模拟技术计算研究的微观结构与界面自由能等热力学量在过去二十年中取得了巨大进步。然而，这些进步局限于匀质固-液界面体系。本项目针对异质Al/Pb合金的固液界面，研究了具有面内台阶毛细波涨落的光滑Al(111)/Pb固液界面。掌握了光滑Al(111)/Pb固液界面台阶与面内液体共存的模拟方法。提出了光滑Al(111)/Pb固液界面界面自由能中的核心变量-台阶自由能的计算方法。掌握了Pb液滴在金属Al表面上的浸润形状和铺展动力学，随温度和液滴尺寸的物理规律。提出了一套超高时空分辨率捕捉粗糙平衡态固-液界面的并行化计算方法。发表论文4篇。