The new manufacturing technology sheet-bulk metal forming (SBMF) combines the sheet metal forming and bulk metal forming techniques. At the Institute of Forming Technology and Machines (IFUM), a new multistage SBMF process is being developed. In order to reduce the friction and improve the dimensional accuracy of the parts, superimposed oscillation is used within the new SBMF process. SBMF processes allow the manufacturing of solid metal components out of flat steel. To analyse the effect of friction on the superimposed oscillating SBMF process more precisely, superimposed oscillating and non-oscillating ring compression tests at room temperature were carried out. Like the semi-finished products for SBMF process the ring specimens were cut out of a sheet plate by water jet cutting. A new tool system with an integrated hydraulic oscillation system was developed for superimposed oscillating compression of the ring specimens. This tool system enables the absorption of the forming force and displacement stroke of the ring specimen during the ring compression test. After the practical experiments, the force profiles of superimposed oscillating and of non-oscillating process were compared. The influence of the frequency on the surface roughness of ring specimens was investigated. Furthermore, the tribological conditions of the superimposed oscillating ring compression test were analyzed.

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Bone regeneration depends on a pool of bone/cartilage stem/progenitor cells and signaling mechanisms regulating their differentiation. Using in vitro approach, we have shown that PDGF signaling through PDGFRβ inhibits BMP2-induced osteogenesis, and significantly attenuates expression of BMP2 target genes. We evaluated outcomes of treatment with two anabolic agents, PDGF and BMP2 using different bone healing models. Targeted deletion of PDGFRβ in αSMA osteoprogenitors, led to increased callus bone mass, resulting in improved biomechanical properties of fractures. In critical size bone defects BMP2 treatment increased proportion of osteoprogenitors, while the combined treatment of PDGF BB with BMP2 decreased progenitor number at the injury site. BMP2 treatment induced significant bone formation and increased number of osteoblasts, while in contrast combined treatment with PDGF BB decreased osteoblast numbers. This is in vivo study showing that PDGF inhibits BMP2-induced osteogenesis, but inhibiting PDGF signaling early in healing process does not improve BMP2-induced bone healing.

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Sheet-bulk metal forming is a manufacturing technology, which allows to produce a solid metal component out of a flat sheet. This paper focuses on numerical and experimental investigations of a new multistage forming process with compound press tools. The complete process sequence for the production of this solid metal component consists of three forming stages, which include a total of six production techniques. The first forming stage includes deep drawing, simultaneous cutting and following wall upsetting. In the second forming stage, flange forming combined with cup bottom ironing takes place. In the last stage of the process sequence, the component is sized. To investigate and to improve process parameters such as plastic strain distribution, resulting dimensions and process forces, FEA is performed. Based on these results the developed process is designed.