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Manufacturing of functional sheet metal products by forming can be realised with the application of conventional bulk forming operations on sheet metals. The challenges of those sheet bulk metal forming processes are high resulting forming forces and the demand on a specific control of material flow. To meet these challenges well-directed thinning of blanks as well as accumulations of material to form functional elements is employed. Due to local loads, simultaneous 2D and 3D stress and strain states occur. Process adapted semi-finished products, containing a defined sheet thickness characteristic, are formed in the presented work by the technologies upsetting and orbital forming. Orbital forming is an incremental bulk forming operation to decrease the forming zone extension and consequently the required process force. Afterwards a process combination of deep drawing and upsetting in order to manufacture a cup-shaped workpiece with external gearing is presented. The results of this integrated single-stage forming process are discussed and subsequently the potential to enhance the process limits is shown by using process adapted semi-finished products.

The standard procedure of a surgical suture can be very difficult to perform in deep-wound cavities because the available space is not enough to perform the complicated movements required for the knot or to handle the needle. To improve this situation a new kind of hollow, helical needle was developed and filed for patent. To ensure the manufacturability of this kind of needle, a prototype and a prototypical tool were designed and tested. As a prototypical basis, commercially available cannulas were selected. Coil winding was used as a forming process to bring the cannula into the helical form. The material properties of the surgical steel and the work hardening that the semi-finished products underwent lead to challenges for the forming process. The limitations of springback and low formability reduce the possible radius of the helix. Therefore, a soft annealing of the cannula was investigated. However, in surgical needles, stiffness is of great importance. Since hardening by quenching is not possible, annealing parameters were chosen to retain the necessary stiffness. Based on the data obtained from tests of annealing parameters, four final geometries of helical needles were designed and first prototypes were manufactured.

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