StaProCrash – Development and manufacture of crash-optimized multi-chamber steel structures by roll forming
In this project, methods for the efficient design of roll-formed, crash-optimized profile structures are being developed. Various high-strength steels are investigated for their behavior during roll forming and their ability to absorb energy during deformation. Based on this, cross-section geometry optimization algorithms designed for extrusion profiles are adapted to optimize the cross-section geometry of roll-formed multi-chamber structures made of high-strength steel. Finally, demonstrators will be manufactured and their behavior in crash tests will be investigated.
Currently, laterally loaded components in automobiles are usually made from welded deep-drawn or body-drawn sheet metal structures or from extruded aluminum structures. Although at first glance aluminum structures have weight advantages over steel structures due to their lower density, they require significantly more material due to their lower strength and are also significantly less recyclable. Deep-drawn or body-drawn components are costly to manufacture and do not save resources due to the comparatively long process time and the necessary blank cutting. Roll forming can compensate for the disadvantages of the above-mentioned processes thanks to its high process speeds, high material utilization and suitability for forming high-strength steels. The use of geometry-optimized roll-formed multi-chamber structures made from high-strength steel could consequently both reduce the weight of crash structures while maintaining the safety of vehicle occupants and conserve resources.
As part of the project, material characterizations will first be carried out with various high-strength steels to determine the influence of roll forming on the strength and the ability of the structures to absorb energy. In addition, roll forming simulations will be performed for different profile cross-section geometries and multi-chamber structures. The data obtained will be provided to the Bergische Universität Wuppertal in order to adapt an algorithm developed for extrusion profiles for optimizing the cross-section geometry to the requirements and material behavior in roll forming. The aim of the optimization is to optimize the cross-section of a roll-formed multi-chamber structure so that the structure can absorb as much energy as possible with as little weight as possible. To validate the optimization result, demonstrators are manufactured from roll-formed components and their crash behavior is investigated in a drop tower. Figure  illustrates the procedure.
The research work presented here takes place within the framework of IGF project no. 23320N of the research association Europäische Forschungsgesellschaft für Blechverarbeitung e.V. (EFB). This is funded by the German Federal Ministry for Economic Affairs and Climate Action (BMWK) via the German Federation of Industrial Research Associations (AiF) as part of the program for the promotion of joint industrial research (IGF) on the basis of a resolution of the German Bundestag.
Furthermore, we would like to thank all industrial partners who support the research project “Profile straightening by partial rolling” in the project accompanying committee.