PNNL

Abstract

Recycling secondary aluminum (scrap) reduces energy consumption by up to 90%, compared to primary aluminum manufacturing. However, traditional recycling pathways are melt-based and impose limitations on alloy compositions, microstructure, and resulting mechanical properties. To address these challenges, we have devised a solid-phase recycling and simultaneous alloying method. This innovative process enabled the alloying of 6063 aluminum alloy scrap with copper powder, zinc powders, and ZK60 magnesium ribbons to rapidly form extrudates of a nanocluster-strengthened high-performance aluminum alloy with composition and properties akin to 7075 aluminum alloy. The unique nanostructure with a high density of Guinier-Preston zones and uniformly precipitated nanoscale ?'/Mg(CuZn)2 strengthening phases enhances both yield and ultimate tensile strength by ~200%. This scalable approach allows the upcycled materials to outperform the original material and can be extended to establish on-demand upcycling of other metallic materials from scrap sources, presenting a sustainable, efficient, clean, and innovative solution for materials recycling.