As the availability of pure and uncontaminated alloys becomes increasingly difficult, recycling is becoming more and more important. It is feasible to separate and remelt scraps through complex sorting, but today’s method contradicts the UN sustainability goals: Aluminum alloys are recycled by adding a large amount of primary aluminum to meet stringent alloy composition and purity requirements. However, primary aluminum is gained through a very energy-intensive electrolysis process, which requires 20 times more energy than the remelting of recycled aluminum. Therefore, it is essential to develop smart and robust technologies which are capable to compensate the influences of alloy variations on the part properties and to use various alloying recyclates for defined property profiles.

There is significant demand for aluminum in the field of e-mobility. Leading car manufacturers are setting on electric drives to reduce CO2 emissions and are undertaking great efforts to increase the range of the cars by consequently reducing the weight. Therefore, major parts, such as battery housings and car bodies, are made from the damage-tolerant light metal. With respect to sustainability and resource efficiency these needs can only be satisfied by increasing the recycling intensity.

This is the starting point for the presented research activity, in which a resilient manufacturing process for damage-tolerant parts from unpurified aluminum recyclates is to be developed. Due to the higher degrees of freedom in comparison to conventional manufacturing technologies, the process chain of the laser powder bed fusion (LPBF) based additive manufacturing is selected. Here, the interrelations between the manufacturing process, the forming microstructure and the resulting mechanical properties are investigated in detail by using nano- and microanalytical methods. Starting point is the atomization of aluminum recyclates into powder for additive manufacturing. On this basis, a material-oriented additive manufacturing approach is developed to produce pore-free parts with homogenous mechanical properties. This approach is supported by a load-adapted design of the part. The process development is accompanied by a digital representation of the entire process chain from the recyclate to the complex final part.

The presentation gives a general overview about the different research aspects investigated and insights into the first results obtained.