Coordinated by the Helmholtz Center Hereon, research and industry are working together on more environmentally friendly production of lightweight components for the automotive industry. The “S3-ALU” joint project funded by the Federal Ministry of Economics and Climate Protection (BMWK) will test the replacement of pure aluminum with recycled aluminum, which could reduce the CO2 footprint per vehicle by 55 percent.
Aluminum and CO2
22,000 tons of CO2 – that is the footprint of the SUVs produced in Germany every day. Part of this is due to the material used: aluminum or primary aluminum. This pure form of aluminum is produced directly from the raw material bauxite and is the main component of alloys used in automotive production thanks to its advantages in terms of weight and corrosion properties. A coalition of research and industry is now investigating the possibility of replacing the primary aluminum previously used with secondary aluminum, i.e. impure, recycled aluminum – without losing the beneficial properties.
The savings potential is enormous: to produce one unit of secondary aluminum, only five percent of the energy is used compared to the production of primary aluminum. Applied to automobile production, this means a saving of 0.7 tons of CO2 per vehicle or 700,000 tons of CO2 for the annual production of SUVs in Germany. Aluminum is being used more and more in electric vehicles, for example to offset the weight of the battery. This intensifies the need to examine and optimize more climate-friendly alternatives such as secondary aluminum with regard to its application. Current forecasts show that the savings potential with aluminium-intensive construction methods is up to 1.7 tons of CO2 per vehicle.
The digital twin
With the help of a digital twin, different compositions of secondary aluminum are to be modeled in order to find the best possible replacement for the original. The many material variants do not all have to be tested in experiments, but are researched in the model, saving time and resources. Previous investigations have already shown that small impurities in the primary aluminum occur and are still acceptable for the safe use of the material. However, the question is how large can or may the proportion of recycled aluminum be and in what composition? The digital twin can provide the answer.
“The development of a digital twin, i.e. a multi-scale physical representation of the material to be examined – the aluminum secondary alloy – will significantly shorten the experimental efforts and make it possible to use the available scrap of inconsistent quality with regard to possible use in material production or the production,” explains Eugen Gazenbiller, doctoral student at the Hereon Institute for Surface Research.
Joint project “S3-ALU”
The joint project “S3-ALU: Simulation methods for the evaluation of components and systems for sustainable lightweight construction with secondary aluminum” is funded by the Federal Ministry of Economics and Climate Protection (BMWK) with 2 million euros over three years. Research project partners are the Max Planck Institute for Iron Research (MPIE), Access e. V. and the Helmholtz Center Hereon, whose institute for surface research coordinates the project. From the industry, Volkswagen AG, Bode – die Tür GmbH and LGL Bad Langensalza GmbH are involved.
Background: technical details
A digital twin is a virtual representation of a real-world process, object, or material with a mutual connection. This means that changes to the real object flow into the digital twin almost in real time. In the next step, the digital twin can be exposed to different framework conditions and thus in turn represent potential “what if” scenarios of the real object. For example, materials and workpieces can first be tested digitally in different situations without going through the entire production process.