Study on surface generation in nano-cutting by large-scale molecular dynamics simulation

Large-scale molecular dynamics simulations are employed in investigating the nano-cutting process. A cutting tool with 1-μm nose radius and 20-nm edge radius is applied in nano-cutting of silicon with cutting distance attaining 400 nm. The mentioned cutting parameters are relatively larger than those used in the former research studies which would help to obtain the results with relatively high confidence coefficient. The results show that when the UCT is smaller or similar to the stagnation height, the extrusion accompanied with the side flow dominates the material removal mechanism. The generated side flow will deteriorate the generated surface roughness. When cutting at {111}<11-2> direction, bct5-Si phase forms and a part of them is left in the machined subsurface. When cutting at {100}<001> direction, the formed bct5-Si and S-II phases transform to the a-Si phase, when the cutting tool passes through.