扭转载荷作用下铜纳米线的力学性能研究

Study on the Torsion Strength of Copper Nanowires in Different Crystal Arrangement Using Molecular Dynamics Simulation

王锡芝 王永棋 赵孟姣 姜文全

Xizhi WANG Yongqi WANG Mengjiao ZHAO Wenquan JIANG

辽宁石油化工大学 机械工程学院，辽宁 抚顺 113001

School of Mechanical Engineering，Liaoning Petrochemical University，Fushun Liaoning 113001，China

通过分子动力学，模拟研究了铜纳米线在不同晶向（I：x[1 0 0] y[0 1 0] z[0 0 1]，Ⅱ：x[1 0 1/8] y[0 1/8 0] z[－1/8 0 1]，Ⅲ：x[1 0 1/4] y[0 1/4 0] z[－1/4 0 1]）、不同晶体内外直径比（ α1=1/6，α2=1/2，α3=5/6）、不同孪晶界面个数（0，2，4）下的扭转变形行为，以及铜纳米线在扭转过程中的剪切应力与扭转角之间的关系。结果表明，改变晶向类型，有助于提高铜纳米线的扭转力学性能；减小晶体内外直径比，可以改善铜纳米线的扭转力学性能；减少孪晶界面个数，对铜纳米线的扭转力学性可起加强作用；铜纳米线的扭转过程分为弹性、塑性和变形破坏三个阶段。研究结果可为高强度铜纳米材料扭转的研究提供依据。

Through molecular dynamics simulation, the torsional deformation behavior of copper nanowires in different crystal orientations (Ⅰ: x[1 0 0] y[0 1 0] z[0 0 1], Ⅱ: x[1 0 1/8] y[0 1/8 0] z[－1/8 0 1], Ⅲ: x[1 0 1/4] y[0 1/4 0] z[－1/4 0 1]), different crystal orientation ratios (α1=1/6, α2=1/2, α3=5/6), and different numbers of twin interfaces (0, 2, 4) were studied, as well as the relationship between the shear stress and torsion angle of copper nanowires during torsion. The results indicate that change the orientation type contributes to enhancing the torsional mechanical properties of copper nanowires. Reducing the ratio of internal diameter to external diameter also improves the torsional mechanical properties of copper nanowires. Furthermore, decreasing the number of twin interfaces can strengthen the torsional mechanical properties of copper nanowires. The torsion process of copper nanowires can be divided into three stages: elastic, plastic and deformation failure. The research results provide a basis for investigating the torsion of high?strength copper nanomaterials.

辽宁省教育厅科学技术研究项目(LJKMZ20220725)

10.12422/j.issn.1672-6952.2024.04.009