Dynamic Interactions and Deformation Mechanisms in Nanocutting of Carbon Nanotube Reinforced Ni-Based Composites

Molecular dynamics simulations were employed to investigate the effects of cutting speed and cutting depth on the nanocutting behavior of carbon nanotube (CNT)-reinforced Ni composites. The results show that increasing cutting speed from 50 to 200 m/s reduces the average tangential cutting force by approximately 16.5%, while the cutting temperature increases by 26.7% at a cutting distance of 200 Å. Cutting depth produces a stronger influence on subsurface deformation, with deeper cutting accompanied by increased stress localization, structural disorder, and dislocation activity. In contrast, dislocation evolution exhibits a non-monotonic dependence on cutting speed, indicating that thermal and mechanical effects act concurrently under different cutting conditions. Pronounced changes in local deformation and dislocation behavior are also observed near the CNT–matrix region. These results characterize the coupled thermomechanical and defect responses of the selected CNT–Ni system under different nanocutting conditions.