Modelling and simulation of surface topography in ultra-precision diamond turning

This paper describes a model for the simulation of surface topography in ultra-precision diamond turning. In the model, the kinematics of the diamond turning process is characterized by machining parameters, the tool geometry as well as the relative motion between the tool and the workpiece. The topography of the machined surface is generated by a linear mapping of the predicted surface roughness profiles on the surface elements of a cross lattice. A series of cutting experiments was carried out. Good correlation is found between the simulated topography and the three-dimensional topography obtained from the optical interferometer. The model can be used for the optimization of the diamond turning process without the need for costly trial-and-error cutting tests. With the use of equi-contour mapping techniques, the model can also help to identify surface features like traces of tool motion and surface waviness. Potential applications of the modelling technique to other processes and tool and workpiece combinations are also discussed.