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Due to rising demands regarding the functionality and load-bearing capacity of functional components such as synchronizer rings in gear systems, conventional forming operations are reaching their limits with respect to formability and efficiency. One way to meet these challenges is the application of the innovative process class of sheet-bulk metal forming (SBMF). By applying bulk forming operations to sheet metal, the advantages of both process classes can be combined, thus realizing an optimized part weight and an adapted load-bearing capacity. Different approaches to manufacturing relevant part geometries were presented and evaluated regarding the process properties and applicability. In this contribution, a self-learning engineering workbench was used to provide geometry-based data regarding a novel component geometry with circumferential involute gearing manufactured in an SBMF process combination of deep drawing and upsetting. Within the comprehensive investigations, the mechanical and geometrical properties of the part were analyzed. Moreover, the manufactured components were compared regarding the increased fatigue strength in cyclic load tests. With the gained experimental and numerical data, the workbench was used for the first time to generate the desired component as a CAD model, as well as to derive design guidelines referring to the investigated properties and fatigue behavior.

Pin extrusion is a common process to realise pin structures in different geometrical dimensions for a subsequent joining operation. Nevertheless, the process of pin extrusion offers process limits regarding sheet thinning as a consequence of the punch penetration depth into the sheet. Thereby, cracks at the residual sheet thickness can occur during strength tests, resulting in a failure of the complete joint due to severe thinning. Therefore, measures have to be taken into account to reduce the thinning. One possibility is the application of orbital formed tailored blanks with a local material pre-distribution, which allows a higher sheet thickness in the desired area. Within this contribution, the novel approach of a process combination of orbital forming and pin extrusion is investigated. To reveal the potential of a local material pre-distribution, conventional specimens are compared with previously orbital formed components. Relevant parameters such as the residual sheet thickness, the pin height as well as the average hardness values are compared. The results show a significant positive influence of a local material pre-distribution on the residual sheet thickness as well as the resulting pin height. Furthermore, the strain hardening during orbital forming can be seen as an additional advantage. To conclude the results, the process limits of conventional pin extrusion can be expanded significantly by the application of specimens with a local material pre-distribution.

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Contrary demands like a reduction of carbon dioxide emissions and an increase in functionality are facing the manufacturing industry with growing challenges. When processing functional components, like synchronizer rings, conventional process chains, like shearing and subsequent joining, are reaching their limits due to an increased complexity of the components and a lack in efficiency, referring to the long process time. To meet these challenges, the strategy of lightweight construction combines the application of lightweight materials with efficient manufacturing processes and an innovative product design. One possibility within lightweight construction is the utilization of load-adapted hybrid components, featuring different material strength classes. In previous research, the process of orbital forming is used to manufacture semi-finished products with a varying thickness profile due to the specific radial material flow. This material flow should now be used to realize a permanent joint between materials of two different strength levels. Therefore, the process of orbital forming is modified to manufacture hybrid semi-finished products from a dual-phase steel DP600 and a naturally rigid aluminum alloy EN AW 5754, both with an initial thickness of 2.0 mm. Different joint geometries are cut by laser into a steel ring and the part is coaxially positioned around a basic aluminum disc inside a die and subsequently formed. The joint is investigated regarding the geometrical and mechanical properties, comparing a radial cross-section and the micro hardness distribution. In order to reveal the potential of orbital forming for a combined forming and joining operation, the axial as well as the peeling strength of the multi-material components are investigated and evaluated.