Simulation of force, energy, and surface integrity during nanometric machining by molecular dynamics (MD)

Mechanical tribology is the key research object in the process of materials machining. The machining process will produce inevitable surface and surface damage, which is directly related to the relative motion between tool and workpiece. Moreover, in case of precision machining, there are limitations of existing measurement technique on observation of nanoscale materials removal mechanism. Therefore, a numerical simulation method is needed to observe various physical phenomena at the nanoscale and carry out microscopic interpretation. Microcosmic interpretation can guide the manufacturing process and predict possible problems. Molecular dynamics (MD) is considered to be one of the most suitable numerical simulation methods. MD method was used to simulate the whole machining process and analyze the changes of various machining parameters in the process, so as to predict and guide the machining process. In this chapter, the application of MD in tribology is systematically described by describing the important parameters in modeling and machining. Potential energy function, model size effect, boundary condition, machining parameters, and tool geometry parameters in MD machining model are discussed. The materials removal is related to the cutting force, energy, and frictional coefficient in MD model. Residual stress, surface and subsurface damage can also be evaluated by MD machining process.