Theoretical and experimental investigations on the influence of the microscopic anisotropic material properties of gear teeth on their macroscopic behavior

Innovative cold rolling technologies are important future production methods to gain more resource efficiency producing gears. Through current research at the Fraunhofer Institute for Machine Tools and Forming Technology (IWU), it is possible to produce running gears for use in vehicle transmissions by this method. The paper contends theoretical and experimental investigations on cold rolled gears to determine their properties in detail. The theoretical principles of material anisotropy following cold forming processes as well as the results of investigations on gear teeth are discussed. Different calculation methodologies to compute the efficient elastic behavior of an anisotropic material area are compared by applying them to measurement data of an Electron Backscatter Diffraction (EBSD). Furthermore, methods to simulate the rolling process are described and applied to the investigated gear. It is shown that the production method can have an effect on the elastic material behavior of gear teeth.