Fundamental investigations on the production of functional components from coi

• Applicant: Professorin Dr.-Ing. Marion Merklein
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: from 2021 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 471835637

Lightweight construction, motivated by growing ecological requirements as well as economic reasons, results in an increasing demand for functional integrated components. Sheet-bulk metal forming is particularly suitable for the economical and ecological production of functional components in short process chains. The process is defined as the application of bulk forming operations on sheet metal, often in combination with sheet metal forming, to produce components with integrated functional elements by means of a three-dimensional material flow. Extensive process knowledge has been gained in recent years. In previous research, almost exclusively precut blanks have been utilized. Contrary, coil as a semi-finished product has numerous advantages over blanks. On the one hand, previous research has shown that the geometrical accuracy of the functional elements is improved by the additional stabilizing effect of the not yet trimmed material. In addition, higher die filling is possible by supplying material from areas not cut at this stage. A further significant advantage is the higher output quantity compared to blanks, due to the possibility of forming from the coil with a progressive die and the omission of cycle time-limiting gripper systems. On the other hand, the central challenge of using coil is an anisotropic material flow, which limits geometrical part accuracy and results in fatigue critical tool loads.In this context, the present research project aims to develop a fundamental process knowledge for sheet-bulk metal forming of gearings from coil. For this purpose, two extrusion processes will be designed and used for experimental and numerical investigation on the causes of the anisotropic material flow and its effects on the component accuracy as well as on the tool loads. The similarities and differences to extrusion of pre-cut blanks will be determined. Based on the acquired understanding, workpiece-, process- and tool-related measures will be analyzed to meet the coil-specific challenges by means of material flow control. Therefore, their effect mechanisms as well as their impact on component accuracy and tool loads are investigated. High tool life is necessary for efficient production from coil. Consequently, the potentially wear-critical measures are examined in tool life investigations regarding their functional stability. By combining the findings regarding the material flow during forming from coil and measures to meet the challenges the process limits are determined and a fundamental process understanding for extrusion of gearings from coil is created.

• DFG Programme: Research Grants