Investigation on mechanism of ultraprecision three-body polishing of single-crystal silicon carbide with voids by molecular dynamics simulation

The existence of a void will affect the mechanics of the polishing behavior. Therefore, this paper investigated the mechanism of ultraprecision three-body polishing of a single-crystal cubic (3C) silicon carbide workpiece with voids using molecular dynamics simulation. The effects of void size, void shape, void arrangement, and the number of voids on the workpiece during polishing were studied. The results showed that structural transformation is the principal mode of chip formation at the nanoscale. The polishing force and normal stress are reduced when polishing the workpiece with voids, thereby weakening the strength and the ability to resist deformation of the material. In addition, the surface/subsurface damage of the workpiece with voids is exacerbated. The plastic deformation of the workpiece with voids is strengthened due to the high dislocation density, and the atomic removal is improved. This article provides significant guidance for a more thorough understanding of three-body polishing brittle material.