Wang Quanlong, Zhang Chaofeng, Wu Meiping, Chen Jiaxuan
School of Mechanical Engineering, Jiangnan University, Wuxi, 214122, People's Republic of China.
Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment &Technology, Wuxi, 214122, People's Republic of China.
Nanoscale Res Lett. 2019 Jul 17;14(1):239. doi: 10.1186/s11671-019-3065-0.
The effect of fluid media on material removal and subsurface defects evolution in nano-cutting process of single-crystal copper is investigated by means of molecular dynamics simulation. In this paper, the removal mechanism of the chip and formation mechanism of machined surface are investigated by analyzing the atomic migration and dislocation evolution of workpiece during nano-cutting process with the use of aqueous media. The distribution of temperature and subsurface defect crystal structural transformation are investigated, which are analyzed by centro-symmetry parameter and common neighbor analysis methods. The results show that the workpiece material is removed by the extrusion shearing action of the cutting tool. The lubrication of the aqueous media can reduce the cutting force and lower the height of cutting chip. Particularly, the cooling action of the fluid media results in the formation of a typical defect "similar-to-grain boundary" in subsurface of the workpiece. And the temperature of workpiece has a distinct decrease during nano-cutting process with the use of fluid media.
通过分子动力学模拟研究了流体介质对单晶铜纳米切削过程中材料去除和亚表面缺陷演变的影响。本文利用水性介质，通过分析纳米切削过程中工件的原子迁移和位错演变，研究了切屑的去除机理和加工表面的形成机理。研究了温度分布和亚表面缺陷晶体结构转变，采用中心对称参数和共同邻域分析方法进行分析。结果表明，工件材料通过切削刀具的挤压剪切作用被去除。水性介质的润滑作用可以降低切削力，降低切屑高度。特别是，流体介质的冷却作用导致工件亚表面形成典型的“类晶界”缺陷。并且在使用流体介质的纳米切削过程中，工件温度有明显下降。
