POTENTIAL OF CARBIDE TOOLS FOR HIGH PERFORMANCE HOBBING

摘要

To match the future goals of higher productivity and lower production costs, the cutting speeds and feeds in modern gear hobbing applications have to increase further. In several cases, coated carbide tools have substituted the commonly used HSS tools. Because this leads to production processes working on the upper level of their performance opportunities, the tolerances for deviations from the optimum process settings are getting smaller. To match with this situation, especially in carbide hobbing, all factors that have an influence on the hobbing process like the workpiece geometry, the process parameters and especially the tool design have to be taken into account if a high level of process performance is desired. This essay will present a case study based on two industrial gearings. The investigations include the influence of the tool design concerning coating, substrate, layout and edge preparation on the tool performance. In detail, fundamental base line trials using the analogy process "fly-cutter hobbing" will be presented. Besides several coating and substrate combinations also different tool layouts have been tested. To verify the results, real hobbing trials under industrial production conditions have been carried out as well. Finally, the potential of modern simulation and calculation programs to optimize hobbing processes will be shown. The report aims to give new impulses to the tool design of carbide hobs and an optimized process setting.