Surface Morphology of Laser-Assisted Nanomachining of Silicon Carbide

Silicon carbide is a typical hard and brittle semiconductor material that is prone to high cutting resistance, surface defects, and subsurface damage during nanomachining. To reveal the atomic-scale material removal mechanism of 3C-SiC under low-power laser heating, a molecular dynamics model of single-crystal 3C-SiC cut by a diamond tool was established, and conventional cutting was compared with laser-assisted cutting. Under low-power laser irradiation, the evolution of system potential energy was generally similar to that observed in conventional cutting, indicating limited overall thermal disturbance. The average cutting force decreased from approximately 285 nN to 275 nN, while the maximum burr height was reduced by about 0.75 Å. In contrast, the chip pile-up height increased by approximately 1.68 Å, and the temperature under laser-assisted cutting was slightly higher than that under conventional cutting. The results indicate that moderate laser-induced thermal effects enhance atomic migration in the cutting region, reduce the resistance to material removal, and improve the flatness and edge quality of the machined surface. These findings provide theoretical insight into the mechanisms of the laser-assisted nanomachining of 3C-SiC.