Abstract: The molecular dynamic method is employed to simulate the grinding process of defect-free monocrystal silicon, explain the micro-scale mechanism of material removal, surface generation and sub-surface damage, and then analyze the grinding force and the grinding energy dissipation on atomic scale. The research shows: Some silicon atoms are deformed and piled up in front of the abrasive because of the abrasive’s extrusion and cut. When the energy in silicon lattice reaches its maximum value, the bonds of silicon atoms are broken and the material is removed. With the advancement of the abrasive, the silicon lattice under the abrasive is fractured, and then the amorphous layers are formed and propagated, which causes the sub-surface damage. At the same time, some amorphous atoms are reconstructed and the degenerating layer of the machined surface is formed.

Key words: Machining mechanics, Molecular dynamic simulation, Ultra-precision grinding