Magneto-abrasive machining for the mechanical preparation of high-speed steel twist drills

In this paper investigations of the influence of magneto-abrasive machining (MAM) on the micro-geometry of the tool cutting edges and the surface quality of high-speed steel (HSS) twist drills are presented. It is shown that MAM makes it possible to reproduce defined radii of the cutting edges and corner edges of the drills and improves the tool surface quality. The optimally rounded cutting corner edge of the drill makes it possible to avoid the run-in period of the drill and increases the stability of the cutting edge substantially. This results in an improved wear behaviour and higher tool life of the drill.