New applications for casts emerge in the e-mobility such as motor housings, gearboxes and gear covers of electric power trains. The HPDC process is ideal for the production of such complex lightweight parts. By increasing the amount of recycled aluminum used a reduction of the carbon footprint within the manufacturing, operation and recycling phase can be achieved. Using high strength Al-alloys lowers the material needed leading in a further reduction of weight and carbon footprint. Lastly, by using refined casting processes such as Vacural®-casting from Oskar Frech GmbH, the quality of a cast can be increased further reducing the material required.

These three actions are combined in the project “InDrutec-E“. Funded by the German Federal Ministry for Economic Affairs and Energy, the project investigates the influence of high recycling content on the mechanical properties of three modified primary Al-alloys for structural casting. The resulting secondary alloys have widened tolerance intervals of alloying elements like copper, silicon, iron or zinc allowing to increase the recycling rate. Simultaneously, the effect of the casting technology is investigated by comparing regular with vacuum assisted as well as with Vacural® HPDC. The results are then matched with their base alloys and with the alloy AlSi10Mg(Fe).

For this study, test samples for tensile tests were produced and the mechanical properties determined in a full factorial manner.

This lecture shows a selection of results and highlights the different characteristics determined in tensile tests of the modified alloys and their base counterparts as well as the influence of the different casting processes. Porosity analysis of record CT scans and density measurements provide information on defect volume. Metallographic investigations depict the microstructure formation of primary compared to secondary alloys. By passing on the findings, the lecture thrives to achieve a wider use of recycled aluminum for HPDC.