应用分子动力学方法模拟了带孔纳米单晶铜悬臂梁的弯曲过程。通过一端固定另一端施加横向作用力驱使原子运动,得到纳米单晶铜悬臂梁弯曲的变形图。对其不同于宏观连续介质理论的位移.载荷曲线进行分析。给出了合理的解释。结果表明:纳米尺度下的微缺陷对纳米单晶铜悬臂梁的性能具有明显的影响;尺寸效应和表面效应的影响,以及位错滑移和弛豫的综合作用,使得纳米单晶铜悬臂梁在纳米尺度下表现出与宏观尺度下不同的力学特性。
The bending process of a single crystalline nano-copper cantilever beam with holes was simulated by using the molecular dynamic method. The atomic movement of the cantilever beam was motivated by transverse force on one end while another end was fixed, through which its bending deformation image was obtained. The displacement-load curves that are different from the macro-continuum medium theory were analyzed and explained. The results show that the tiny defects in nanoscales have obvious effects on the performances of the single crystalline nano-copper cantlicver beam. The compositive impact of size effect, surface effect, dislocation, slip and relaxation explains the reason why the single crystalline nanocopper cantilever beam has different mechanical properties in nanoscales from that in macroscopical scales.