Studying the dynamics of cutting process by a face mill cutter

Abstract

Abstract An overview of stepped end mills use for rough cutting of large allowances and finishing cut of flat surfaces is given, where they ensure a reduction in cutting forces, an increase in dynamic stability and performance rate. The study of oscillations in the direction of the longitudinal feed of the spindle and workpiece subsystems, as well as the spindle torsional subsystem, has been carried out by the simulation modeling method. Detailed pictures of the oscillations of these subsystems are obtained. Careful analysis of these oscillations using the basic principles of the regeneration theory of self-oscillations allows establishing their nature and mutual influence. It is established that the main reason for the increased dynamic stability of the stepped end mill as compared to the standard one is the reduction of the power load due to the group cutting scheme and an increase in the uniform distribution of the frequency spectrum of the cutting moment due to the variability of the actual angular pitch of the teeth. The revealed pattern serves as a methodological basis for the creation of progressive designs of stepped end mills. When developing them, it is necessary to look for new patterns of the relative position of the teeth when varying the difference in diameters of the stages and angular steps.