ReCIMP – Research Center for Industrial Metal Processing

Head   Dr.-Ing. Sebastian Wernicke

The cooperation with the international automotive supplier Faurecia, which has been established more than seven years ago, was successfully continued in 2020. In the Research Center for Industrial Metal Processing (ReCIMP) the IUL cooperates with Faurecia’s divisions Automotive Seating and Clean Mobility in various projects in the field of innovative metal forming processes. The superordinate objective of each project is to improve and deepen the basic knowledge about the processes and process chains under investigation. In addition, there is a focus on the identification and investigation of new scientific directions of research in the field of manufacturing technology. Cooperation with other industrial companies and research institutions to build up a competence network is a welcome side effect.

Structurally, the individual ReCIMP projects are assigned to the following six priority areas:

• Extension of forming limits
• Characterization of advanced steel grades
• Alternative production methods
• Flexible production
• Lightweight structures
• Processing of tubes

The project work is performed by scientists from the various IUL departments on a subject-specific basis. The Advisory Board of ReCIMP regularly discusses the progress of the individual projects as well as the overall strategy of the research center. The following figure gives an overview of the projects carried out in 2020.

The researchers are supported by a large number of student assistants and students preparing project or final theses in the projects. Since the establishment of the research center, far more than 60 students have been involved in ReCIMP projects; for several current scientific employees of the IUL, a thesis in ReCIMP was the first step towards their scientific career. In 2020 alone, six project, bachelor, and master theses were written in the research center.

The cooperation is particularly effective when the research topics initially dealt with within the research center lead to fundamental questions and research fields for externally funded projects – this has already happened several times in the past years.

Research projects worked on in 2020

In the field of characterizing modern steel grades, the investigations on the evaluation of global and local ductility were continued in 2020. Depending on the manufacturing process chain, one of the two properties is more important than the other. However, there are also cases in which a balanced relationship between global and local formability is of interest. The measurement of the parameters requires new approaches and was investigated in the project “Ductility analysis of high-strength steels and stainless steels” of various steel grades for applications in the areas of “seating technology” and “exhaust tract”.

Animated by the raising political effort towards the reduction of C02-emissions, ReCIMP initiated a new project in 2020 focussing on the emissions in metal forming process chains. The first steps of the project “Green Manufacturing” are the identification of political and industrial efforts and developments. With two exemplary metal forming process chains, the project goal is to analyze the emissions of sub-processes and to determine the corresponding CO2 saving-potential. Current investigations concentrate on an analytical approach for the prediction of CO2-emissions for the future process design.

In 2020, the project “Processing of materials with wall thicknesses below 0.8 mm” focusses on structured sheet material. The numerical process design for the structured sheets requires knowledge about the forming limits of this material. Therefore, the work in this project addresses the determination of forming-limit-diagrams (FLC) of such structured sheets. The measurement of the local strain during conventional material characterization is identified to be the major challenge in this project (chapter 2.4.12). Due to the structure of the sheets, the crack-initiation happens to occur non-reproducibly and is, thus, usually beyond the range of the optical strain measurement. Consequently, the FLC-determination is not feasible for all observed sheet structures. Moreover, the FLC-determination is limited to only a few strain states.

Beside sheet materials, ReCIMP also considers the forming of tube materials. Emphasis is to be put on non-round tubes as their impact, for example in exhaust systems, increases due to limitations in the assembly space. In the project “Understanding shape deviations for non-round converter design – shape prediction and improvement for the expansion of non-round tubes” a numerical model of the forming process was developed and validated in 2020. The current investigations deal with the subsequent canning process (chapter 2.2.9). With this canning processes the preformed tubes become a component of the exhaust system. During the canning process a sensitive monolith is surrounded by a soft-material and inserted into the preformed tube. This leads to an undesired deformation of the oval tubes. Therefore, the progressive investigation incorporates the numerical implementation of the canning process. Numerical modeling of this process will support the improvement of final shape deviations as well as the load distribution on the sensitive monolith. The numerical consideration of the soft material, which surrounds the monolith, appears to be the most challenging task of further investigations.