SOME POSSIBILITIES OF CHATTER NUMERICAL CONTROL IN CUTTING PROCESSES

The cutting process is inherently affected by chatter, more or less obvious. The chatter may lead to negative effects concerning the generated surface quality, the cutting tool life or the machining precision. In this paper there is considered the case when the self-excited vibration caused either by the regenerative friction and plastic deformation forces variation and/or by the regenerative chip thickness periodic variation, is the chatter main component. A method of evaluating this chatter component, separately from the rest of them, is suggested. Moreover, the method allows an early detection of the regenerative instability, before it produces negative consequences. It could be further used to conceive a new numerical control function, which will keep the machining system operating point as close as possible to the stability limit. This will lead to productivity maximisation, because in almost all practical situations, backing away the operating point from the stability limit implies the cutting regime intensity diminution.