New plunge milling cutter and two-dimensional cavity process based on dislocation chip-separation principle

Plunge milling, as a recognized high-efficiency metal cutting process, is an ideal choice for roughing machining of deep groove and cavity parts. However, due to the severe cutting load of plunge milling, especially the problem of plunge milling collision, and the lack of cavity plunge milling process, its engineering application has always been unsatisfactory. In this paper, starting from the cutter design, the inward-inclined structure of cutting edge is proposed, which can effectively avoid the sharp increase in cutting load caused by plunge milling collision, and realize in situ cutter retraction. At the same time, the dislocation chip-separation structure of cutting edge is also proposed, which can effectively reduce the plastic deformation of cutting layer, and the maximum cutting force is reduced by about 55%. Based on the design of the above high-performance plunging cutter, considering the constraints of material residue and isolated corner, the plunging milling process strategies for open cavity, semi-closed cavity and closed cavity are planned. Finally, the influence law of machining parameters on cutting force is explored. The setup series of verification experiments show that the inward-inclined structure and dislocation chip-separation structure of plunge milling cutter are reasonable, and the process strategies and machining parameters of cavity plunge milling are feasible. Compared with the traditional layer milling, the machining efficiency is increased by about 3.3 times.