The increasing variant intensity in small series, the reduction in the time-to-market in development, and the demand for material efficiency are all opportunities for introducing metal 3D printing in the automotive industry. This is why the EDAG Group, the world’s largest independent engineering service provider for the automotive industry, and nine leading partners, are carrying out the StaVari research project into a fully integrated process chain for the additive manufacture of complex components using an innovative steel grade.
As part of the StaVari research project, a steel alloy tailor-made for car body applications was defined and a new powder alloy was developed which, in the laser-additively processed state, has properties comparable to those of the classic DP800 dual-phase steel. This is a starting point in significantly reducing costs (by as much as 60%) compared to conventional alloys.
Together with its partners, the EDAG Group specified requirements, developed concepts for component design, developed material parameters, material maps and CAE design methods. The partners demonstrated the new powder alloy’s viability and implemented it in the overall project for the production of typical body components.
Powder production, the additive manufacturing process, thermal treatment and post-processing were developed for use in the laboratory, and then scaled up to industrial proportions. New strategies were also developed for joining laser-additively produced components. As a result, intelligently cooperating robots were able to efficiently join laser-additively manufactured steel components in a camera-controlled MAG welding process in which little tooling was used and tolerances were carefully balanced out.
As a demonstrator, the EDAG Group engineers designed a heavy-duty, variant-intensive vehicle structure, which has now been manufactured in close cooperation with all project partners. There are plans to test the demonstrator in a real test as the project progresses.
The demonstrator consists of an LAM-manufactured B-pillar foot reinforcement and a load path-compatible C-pillar node. The bionic structure and the load level-specific functions open up new approaches. In general, StaVari opens up new perspectives for the automotive industry to shorten the time-to-market for prototypes and small series for steel-based bodies in small and medium quantities. Some examples include passenger cars with alternative drives, commercial vehicles, two-wheelers, construction machinery or rail vehicles.
Along with EDAG Group, the partners Ziehm Imaging, Salzgitter Mannesmann Forschung, Cloos, Concept Laser, hema electronic, Indutherm, IWT Bremen, Fraunhofer IAPT and SLK TU Chemnitz are all working on the project, which will be funded by the German Federal Ministry of Education and Research (BMBF) through April 2020.