Influence of friction on the material flow during precision forging of helical gears

摘要

At the Institute of Metal forming and Metalforming machine tools (IFUM) ,University of Hannover ,helicalgearwheels are produced from cylindrical billets using singlestate precision forging processes .For a process integrated heattreatment ,the workpiece materials need to be carburized alreadybefore the forming operation .Thus ,in contrast to conventionalmanufacture ,an inhomogeneous case depth distribution isobtained resulting from the material flow during forming .Anumerical process simulation with the finite elementmethod(FEM) enables to predict this distribution along the shapeo the teeth .The performed experimental and numericalinvestigations illustrate the influence of friction conditions onthe material flow and thus its influence on the case depth distribution.