First online: 15 September 2015

 

Abstract

The forced periodic vibrations of milling processes with helical tools are modelled and analysed. By means of analytical and numerical techniques, the so-called superchart of milling is constructed that includes the conventional stability chart with the stability lobes and also the amplitudes of the stable forced vibrations, which is correlated to many surface quality numbers like surface location error, surface waviness and surface roughness. The existences of trivial and non-trivial appropriate axial immersions are presented for a single degree of freedom mechanical model of the machine tool structure. At these appropriate axial immersion parameters, if the cutting is stable, the surface quality parameters will be also optimal even in those spindle speed domains where the system is near to resonance and the cutting efficiency is high. Experiments are performed with a large industrial milling machine using a flexible test rig with an essential flexibility in one direction. The calculated and the measured forced vibration signals in the stable domains of the stability chart are in good correlation, which validates the simple analytical predictions for the non-trivial appropriate axial immersion parameters.