Starting with sheet metal production, the team at the Institute of Metal Forming at TU Bergakademie Freiberg relies on innovative processes: "The casting rollers used already enable the production of magnesium sheets with thicknesses of around five millimetres. This means that downstream forming steps can be reduced." The result is magnesium components that are around a third lighter than common aluminium solutions while retaining comparable strength. This means that the potential of magnesium as a lightweight material can be better utilised in the future - for example in e-mobility, mechanical and vehicle engineering or medical technology.

Three building blocks for more efficient and climate-friendly magnesium processing

As the first component of the new manufacturing process, the researchers developed technologies that can replace fossil fuels with up to one hundred percent climate-neutral hydrogen. 

A second lever lies in the significantly shortened process route. The team relies on the casting-rolling process integrated at the Institute of Metal Forming to quickly convert the liquid magnesium melt into a preliminary product. The heat from the casting heat is utilised directly for forming, resulting in sheets or wires that already have almost the desired component shape. Energy and time-consuming downstream process steps can thus be reduced.

For wire production, the research team also developed the GieWaCon process, which combines wire casting rolling with the CONFORM™ process. The latter is already established for materials such as copper and was applied to magnesium for the first time in the project. As the CONFORM™ process works at room temperature, the heat present in the casting process can be utilised to directly manufacture a wire product in just a few process steps. The magnesium wires produced in the project achieved a final diameter of 1.6 millimetres - either directly using the CONFORM™ process or through subsequent wire drawing.

In addition, the project shows that the principle of the shortened process route can also be transferred to other forming processes. For example, the magnesium alloy used was successfully forged; the resulting components were reworked immediately after forming, for example by deburring or milling. In addition, an industrial partner developed an extrusion process in which billets are first cast and then extruded from the casting heat. The resulting tube is cut and bent open so that workable sheets can be produced - also without additional heating steps.

The third component used is the calcium-containing magnesium alloy ZAX210. It can be processed well even at comparatively low forming temperatures of around 200 °C and still guarantees stable mechanical properties. "The magnesium alloy allows us to realise forming processes at significantly lower temperatures without compromising on the component properties," explains Professor Ulrich Prahl.

Suitable surface coatings were also investigated for all prototypes in order to ensure corrosion resistance and the usability of the magnesium components under real conditions. In addition, the project team analysed and optimised various welding processes, which were specifically adapted to the magnesium alloy used and further developed for the respective demonstrators.

Together with the industrial partners from the project, the team wants to continue to advance the developed manufacturing routes in the future and apply them to other components and shaping processes. A CO₂ calculator, which companies can use to compile and compare possible process chains for the forming of magnesium, has been specially developed in the project (CLEAN-Mag App: Reducing emissions in industrial processes).