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Processing high strength sheet metal materials causes high tribological loads to the surface of forming tools. To increase the wear resistance and therewith the service time of tools, surface coatings containing hard materials are applied by thermal spraying. In the initial "as sprayed" state, the coatings show a rough surface and porous structure, which is not suitable for sheet forming tools. This article describes the finishing of the coatings by subsequent roller burnishing. By the rolling process surface asperities of the coating are flattened and the contact area between the finished surface and the sheet is increased. Furthermore, residual compressive stresses in the surface zone are generated by the rolling process. The tribological properties of the coated and finished surfaces are analyzed in strip drawing tests with uncoated DP600 sheets varying the contact pressure and drawing velocity. It is shown that the process parameters of the roller burnishing process have a strong influence on the surface topology of the friction elements and their tribological properties. The coated and finished friction elements are compared to conventional grinded steel friction elements, made of C60.

This paper focuses on new forming techniques for the improvement of product quality, the reduction of process chains and the saving of our available resources. The presented and discussed technologies cover extrusion of reinforced profiles, bending of profiles, single point incremental forming of polymers, and tool systems made of polymers coated by hard metal as well as re-manufacturing strategies. Beside the process principles and advantages several results from numerical and experimental investigations will be given in order to show the motivation for fundamental and application oriented research in the field of forming technology.

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The paper concentrates on investigation results dealing with ultra high performance concrete (UHPC) dies for the use in sheet metal hydroforming. A special mixture of UHPC for these tools with its mechanical properties and its manufacturing is presented. The developed UHPC features a compressive strength of approx. 250 MPa and a Young's modulus of approx. 50 GPa. Applying internal pressure, the UHPC die (without confinement or reinforcement) failed between 80 and 96 MPa. The forming test proved a good shape accuracy of the sheet metal parts but revealed critical tribological conditions. Drawing foil and already formed sheet metal parts were tested successfully as interlayer and led to an appropriate material flow and surface quality of the sheet metal parts.