单晶铜纳米切削过程的研究

Study on Nanometric Cutting Process of Monocrystalline Copper by Molecular Dynamics

采用分子动力学三维模型研究单晶铜纳米切削过程 ,工件原子间相互作用力和工件与刀具原子间相互作用力采用Morse势计算 .通过分析切削过程中瞬间原子图像、切削力、单位切削力和轴向切削力与切向切削力比值 ,发现在整个切削过程中有位错产生 ,在加工表面发生弹性恢复 ,但未发生切屑体积的改变 ,切屑以原子团方式去除 ,单位切削力和轴向切削力与切向切削力的比值比传统切削时大得多 .

A three-dimensional model of molecular dynamics (MD) is employed to study the nanometric cutting process of monocrystalline copper. The model includes the utilization of the Morse potential function to simulate the interatomic force between the workpiece and a tool. By analysises of nanometric cutting process, cutting forces, cutting force per unit volume and the ratio of the thrust force to the cutting force, dislocations and elastic recovery behind the tool are observed, but chip volume changes do not appear, and the material removal occurs by the cluster.The cutting force per unit volume and the ratio of the thrust force to the cutting force in nanometric cutting are larger than conventional cutting. Nanometric cutting process of monocrystalline copper is the plastic deformation involving the generation and propagation of dislocations.