Optimisation of face milling operations with structural chatter using a stability model based process planning methodology

Heavy-duty milling processes find productivity limitations due to chatter vibrations related to the dynamic flexibility of the machine tool structure. In high-speed machining, the critical dynamic properties and the resultant process stability are highly dependent on the tool or tool holder and not on the machined part, the machining position or the feed direction. The latter factors have, however, a significant impact on stability of heavy-duty operations, which makes the current stability models unsuitable for the stability prediction of this kind of operations. The present study proposes a standard stability model with specific improvements focused on heavy-duty operations, considering the whole workspace and feed directions. This model is used as the basis for the development of a universal process planning and tool selection methodology. Finally, the proposed method is experimentally verified in two practical cases, where a typical steel roughing operation is successfully optimised for two different machines. The usefulness of the developed methodology is demonstrated.