Effect of tool geometry in nanometric cutting of nanotwinned Cu: A molecular dynamics study

In the present work we investigate the nanometric cutting of a nanotwinned Cu containing 26° inclined twin boundaries using a diamond cutting tool by means of molecular dynamics simulations, with a focus on examining the influence of rake angle of cutting tools on the cutting processes. The underlying deformation mechanisms of the material are elucidated and are further correlated with the evolution of machining forces and the formation of machined surface and chips. Our simulation results indicate that dislocation slip, interaction of dislocation with twin boundaries and twin boundaries-associated mechanisms work in parallel in the plastic deformation of the nanotwinned Cu. It is found that the rake angle has a significant influence on the deformation behaviour of the material, chip formation and machined surface quality. A rake angle of 45° results in smaller energy dissipation and better machined surface quality than the other two rake angles of 0° and -45°.