Investigation of versatile joining processes for the manufacturing of hybrid components in an industrial environment (T01#)

• Subject Area: Joining and Separation Technology ; Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: from 2023 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 418701707

The scope of the project is the analysis of the transferability of the investigated methodology for the versatility of a tumbling self-piercing riveting process within the subproject "Versatile joining with a fastener" in the context of the transregional collaborative research center TRR (SFB/TRR) "Method development for mechanical joinability in versatile process chains" under industrial conditions. Within this context, this versatility should be expanded by target-oriented adaption of relevant process parameters. Central aim within this research project is the transfer of fundamental results for a defined formation of geometrical joint characteristics, like for example undercuts from the tumbling self-piercing riveting process to a novel joining by orbital forming process. Within the SFB/TRR, scientific methods for the versatility of mechanical joining processes and process chains are investigated fundamentally. These results should be applied and transferred onto industrial relevant questions regarding the joining process as well as the component design. The established joining process of self-piercing riveting is combined with an orbital forming process and investigated fundamentally in the scope of the subproject and the technological potential for an increased versatility is evaluated. In this context, the tumbling kinematic, the tumbling angle as well as the chosen joining partners could be identified as significant influence on the forming of undercuts and the rivet head end position and in consequence on the joint quality. Nevertheless, limiting factors prevent a possible industrial application. Due to the use of an additional fastener, the joining direction is a considerable issue besides the increased handling effort. Furthermore, parts with a joint in the sheet metal plane cannot be manufactured. Therefore, the fundamental findings on the geometrical joint formation within the tumbling self-piercing riveting process should be transferred in close cooperation with the involved partners SRAM Deutschland GmbH and C.D. Wälzholz GmbH & Co. KG onto a new joining technique, exclusively consisting of an orbital forming step without additional fastener, under industrial aspects. Besides the use of industrial relevant material classes, a fundamental process understanding of the novel, versatile joining process regarding the occurring interdependencies should be established and a possible later application should be evaluated. By a defined adaption of relevant process parameters, identified in this project, the foundation for a possible application of this new versatile process should be placed. Both partners participate with specific know-how on semi-finished products, material, application, requirements and the evaluation of quality and consequently contributing significantly to the success of the transfer project.

• DFG Programme: CRC/Transregios (Transfer Project)
• Subproject of: TRR 285: Method development for mechanical joinability in versatile process chains
• Applicant Institution: Universität Paderborn
• Participating University: Friedrich-Alexander-Universität Erlangen-Nürnberg
• Business and Industry: C.D. Wälzholz GmbH & Co. KG; SRAM Deutschland GmbH
• Project Heads: Professor Dr.-Ing. Michael Lechner; Professorin Dr.-Ing. Marion Merklein