【摘要】 采用分子动力学三维模型研究单晶硅纳米切削机理,工件原子间相互作用力和工件与刀具原子间相互作用力分别采用Tersoff势和Morse势计算。通过切削过程中瞬间原子图像、能量和切削力的分析,发现在整个切削过程中,发生了非晶态相位的变换和切屑体积的改变,但没有明显的位错和弹性恢复产生。其中切削力的一个分力切向力在非晶态相位变换形成时起主要作用,另一分力轴向力是非晶态扩展的主要因素。单晶硅纳米切削机理不是位错在晶体中运动产生的塑性变形,而是非晶态相位变换产生的变形。更多还原

【Abstract】 A threedimensional model of molecular dynamics (MD) was employed to study the nanometric cutting mechanism of monocrystalline silicon. The model included the utilization of the Morse potential function to simulate the interatomic force between the workpiece and a tool, and the Tersoff potential function between silicon atoms. By analyses of nanometric cutting process, energy and cutting forces, amorphous phase transformation and chip volume change are observed,but dislocations and elastic recovery behind the tool do not appear. Cutting forces initiate the amorphous phase transformation, and thrust forces play an important role in driving the further transformation development. Nanometric cutting mechanism of monocrystalline silicon is not the plastic deformation produced by the generation and propagation of dislocations, but the deformation via amorphous phase transformation.更多还原