Sustainable additive manufactured aluminium components from secondary material for aviation applications (Green-Al-Air)

Increasing the sustainability of aviation and other areas of mobility not only requires the development of environmentally friendly and more efficient propulsion technologies, but also a reduction of CO₂ emissions generated during the production of vehicles. Reducing CO₂ emissions along the production chain is therefore increasingly becoming the focus of research and development. Aircrafts contain a large proportion of aluminium alloys, which as primary variants have a high “CO₂ backpack”. Secondary aluminium (recycled material), on the other hand, can reduce greenhouse gas emissions by up to 95 %. Structural components used in aerospace are also manufactured using machining processes, which require significantly more material than is needed for the final component weight. This buy-to-fly ratio can easily reach values of 5-10. A near-net-shape manufacturing method could contribute to significantly increased material efficiency in this area. Wire and Arc Additive Manufacturing (WAAM) is a suitable option here. This process allows high deposition rates and the realisation of larger structural geometries than would be possible with SLM or EBM processes.

In the ‘Green-Al-Air’ project, aluminium welding wire will be produced from secondary sources, including chip waste from aerospace component manufacturing, and then used in the WAAM process to manufacture components suitable for aerospace applications. The overarching goal of the project is to increase the sustainability of structural components made of aluminium for aerospace applications.

Together with HEGGEMANN AG and MIGAL.CO, the Institute of Materials Science and Engineering I (MSE I) will investigate the microstructure of such components. SEM, TEM and APT investigations will be used to draw conclusions about the optimisation of alloy composition and process parameters. In addition, the mechanical properties under quasi-static and cyclic loading will be investigated. This will be followed by a characterisation of the corrosion behaviour.

The Green-Al-Air research project is funded by the Federal Ministry for Economic Affairs and Energy.