Optimization of Cutting Parameters in Milling by Means of System Nyquist Plot

Abstract

The paper dwells upon improving milling performance. Vibrations in machining represent one of the most significant factors that hinder such performance. Increasing some of the cutting parameters might result in greater vibrations. The so-called Nyquist criterion of dynamic stability is based on the Nyquist plot. On the other hand, the expression to compute the Nyquist plot of the dynamic system of a mill will include all the basic cutting parameters in relation to the cutting process. To determine the values of the Nyquist plot, an experiment is performed, consisting in machining a test workpiece on a milling machine. Cutting is performed once on the low cutting conditions. By using the experimentally found Nyquist plot values, one can build a mathematical model to find the performance-optimized cutting parameters, at which no significant vibrations occur. The proposed method minimizes the labor intensity of tailoring the cutting parameters to a specific production setting.