Impact of Scandium and Zirconium on extrudability, microstructure and hardness of a binary Al-Cu alloy

© 2018 Elsevier Ltd. The aerospace sector is driven by light weighting and stronger and lighter aluminium (Al) alloys are constantly being developed. The use of Scandium (Sc) as an alloying element in Al is extremely promising because of its beneficial influence on Al properties. The impact of Sc on extruded Al is currently unknown. Most aerospace Al alloys have a high Cu content. Hence, we explore the impact of alloying an Al-4wt%Cu model alloy with Sc and Zr. Sc is found to have only minor impact on extrudability. The co-addition of Sc and Zr is found to double the hardness and this is due to a refinement of the grains and the precipitates.