Predictive models of the local and the global polished profiles in deterministic polishing of free-form surfaces

The deterministic polishing process is usually used as the final step to produce part surfaces of high surface finish and form accuracy. This article presents the models of the local and the global polished profiles for the deterministic polishing process when a surface is polished by a spherical polisher. The local polished profile is modeled by integrating the index of material removal, which is defined as the polished depth at unit length of the polishing path, at each tool-surface contact region. According to the model, the local polished profile is determined by the process parameters, the tool attitude, the measuring angle and the geometrical/mechanical properties of workpiece and tool. The linear algebraic expression of the global polished profile is derived by convoluting the local polished depth at each dwell point of the polishing process. The polishing experiments are conducted to verify the proposed model in the different polishing conditions. Moreover, simulation results are given to illustrate the application of the proposed model in optimizing the feed rate to minimize the surface form error in the deterministic polishing process.