Investigations on tailored forming components as tribologically loaded machine elements

To fulfil future trends of machine elements, the surface and part properties need to be enhanced. To advance machine elements, the application of tailored forming technology offers new possibilities. With this approach, it is possible to design and manufacture machine elements consisting of two or more different metallic materials with improved performance and functionality specially adapted to their respective application. The process chain starts with the joining of different materials to multi-metal work pieces, which are subsequently formed close to the final contour. The properties of the joining zone can be improved by thermal and mechanical treatment accompanying the forming process. Exemplary multi-metal components with a boundary zone subjected to rolling contact fatigue were investigated. Thus, an axial bearing, a shaft with an integrated raceway, a bearing bushing/angular contact ball bearing and a bevel gear wheel were in the focus of this research. Here, the highly stressed areas are reinforced with a higher strength material, while the rest of the part consists of a lower grade material. In case of the shaft, the raceway acts like the inner ring of a bearing and should resist rolling contact fatigue and mechanical wear. The process route was set up and simulations regarding the fatigue life in dependence of the layer thickness of the material acting as raceway were performed. First fatigue tests were executed to prove the reliability of the described concept.