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Nowadays, traditional sheet metal and bulk metal forming processes are often reaching their limits, particularly in the automotive sector, if closely-tolerated complex functional components are required. In this paper, an approach for the direct forming of high-precision shapes starting from blanks will be presented and fundamentally analyzed. Aim of this new process-class, named "sheet-bulk metal forming", is the direct forming of functional components with variants out of the sheet. In a first step, the complex interactions between regions of high and low strains, which are characteristic for sheet-bulk metal forming, have been investigated by simulations. Based on the identified process characteristic, new tool geometries and forming strategies for extrusion and deep-drawing processes have been developed to fine-control the local material flow for a defined filling of the target regions. A further enhancement of the mold filling can be achieved by a predistribution of material using tailored blanks with a defined varying thickness where material is transferred to its target regions to adjust special local mechanical properties. In the paper it will be also exemplified, that the desired process behaviour can be supported by local increased friction provided by tailored surfaces.

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Low field permittivity of ferroelectric-ferrite ceramic composites: Experiment and modeling J. Appl. Phys. 112, 094103 (2012) Synthesis and efficient near-infrared quantum cutting of Pr3+/Yb3+ co-doped LiYF4 single crystals J. Appl. Phys. 112, 073518 (2012) Feasibility study in application of forging waste heat on absorption cooling system J. Renewable Sustainable Energy 4, 053109 (2012) Growth of (111) oriented NiFe2O4 polycrystalline thin films on Pt (111) via sol-gel processing J. Appl. Phys. 112, 063908 (2012) Large size metallic glass gratings by embossing J. Appl. Phys. 112, 064505 (2012) Additional information on AIP Conf. Proc. . In most cases the joining has a significant influence on the consecutively forming process due to varying local mechanical properties [3]. Hence the manufacturing of tailored blanks with a defined sheet thickness characteristic by the process class "sheet-bulk metal forming" is investigated. Subsequent the tailored blanks are provided for forming operations such as deep-drawing and the direct forming of complex functional shape elements. Aim of the project is the manufacturing of circular blanks with a sheet thickening in the exterior area by an upsetting operation. At the beginning, FE-based studies and physical experiments using blanks of DC04 are carried out, to create a fundamental knowledge base of the forming process. A comparatively large contact area between blank and forming tool, a threedimensional material flow and the low sheet thickness cause high process forces. Building up a multi-stage upsetting process with different sequenced tool geometries is one approach to meet this challenge. The material flow out of the sheet center is realized step-by-step to lower the actual contact area and sequential the appearing forces.