Simultaneous Optimization of Removal Rate and Part Accuracy in High-Speed Milling

Abstract

High-speed milling provides an efficient method for accurate discrete part fabrication. However, successful implementation requires the selection of appropriate operating parameters. Balancing the multiple process requirements, including high material removal rate, maximum part accuracy, sufficient tool life, chatter avoidance, and adequate surface finish, to arrive at an optimum solution is difficult without the aid of an optimization framework. In this paper an initial effort is made to apply analytical tools to the selection of optimum cutting parameters (spindle speed and depth of cut are considered at this stage). Two objectives are addressed simultaneously, maximum removal rate and minimum surface location error. The Time Finite Element Analysis method is used in the optimization algorithm. Sensitivity of the surface location error to small changes in spindle speed near tooth passing frequencies that are integer fractions of the system’s natural frequency corresponding to the most flexible mode is calculated. Results of the optimization algorithm are verified by experiment.