Abstract
Increasing the post-consumer recycled content (PCRC) of aluminum automotive body sheet (ABS) is a promising pathway to reduce greenhouse gas (GHG) emissions from ABS production. However, progress is constrained by the limited end-of-life vehicle (ELV) ABS scrap available and the compositional mismatches between contaminated scrap streams and alloy specifications. This study identifies cross ABS life cycle strategies that sheet mills, automotive OEMs, and recyclers can implement and quantifies their effects using a composition-specific dynamic material flow analysis to model sheet demand and scrap availability coupled with a linear optimization framework that determines annual PCRC potential under product-demand, scrap-supply, and alloy-composition constraints. A supply chain emissions model links PCRC gains to GHG reductions. By 2050, ABS scrap from U.S. ELVs could supply up to 33% of the ABS ingot demand needed to meet U.S. requirements for ABS components, yet PCRC remains negligible under business-as-usual (BAU) strategies due to compositional incompatibilities. Effective strategies to increase the PCRC include: (1) sheet mills developing high-residual-content (HRC) “recycle-friendly” alloys; (2) OEMs shifting 5xxx-series component designs to 6xxx alloys; and (3) recyclers either extracting sheet-rich sub-assemblies before shredding or adopting advanced sorting technologies to separate shredded ELV aluminum scrap by alloy series. Achieving a PCRC that approaches the physical maximum (33%) occurs only when multiple stakeholders act to implement complementary strategies. The combination of ELV scrap sorting by alloy series and deployment of HRC alloys is particularly effective. Together, these measures could raise PCRC to 28% by 2050, increase total scrap content (including production scrap) to 76%, and cut annual ABS component supply chain emissions by up to 42%.