Researching Nanometric Cutting of Copper Based on Molecular Dynamics

Molecular dynamics simulations are used to investigate the micro-mechanisms of nanomachining for triangle pyramid tip to scratch the surface of single crystal copper {010} plane. The effect of different rake angles and scratching depths on the cutting process was investigated. Through the visualization technique of atomic coordination number, defects in workpiece such as dislocations and stacking atoms are identified under nanoscratching. Their structures and movements are investigated for understanding the mechanisms of defect generation and evolution under various scratching conditions. The analysis of the dynamic features of the substrate shows that dislocations are intrinsically linked to the stress state of atoms in subsurface of workpiece, when stress distribution in workpiece exits the higher gradient fields, which cause the nucleation and emission of dislocations in the substrate region near the tip.