High-temperature behavior of Al alloys for additive manufacturing

Scalmalloy® (Al-Mg-Sc-Zr) was developed specifically for powder bed fusion using a laser beam (PBF-LB) and can achieve high strength when heat-treated due to the precipitation of finely distributed Al₃(Sc,Zr) precipitates. The precipitates are thermally stable up to approx. 350°C, prevent grain growth and allow high strength even at elevated temperatures. However, the magnesium content of Scalmalloy® evaporates during the melting of the powder and disrupts the manufacturing process through smoke, burning, and spattering, which is why another alloy, Scancromal® (Al-Cr-Sc-Zr), was developed. This has similarly high strengths with higher ductility and better process stability. In this project, the influence of the precipitates on the structure and mechanical properties of these alloys is investigated through targeted heat treatments. Particular attention is paid to the high-temperature properties of the materials in comparison to the conventional AlSi10Mg alloy.

The project is conducted at the Ingolstadt University of Technology by Barbara Kneißl as part of a cooperative PhD with the Insitute for Materials Science at UniBw M.