Sustainable Aluminium Recycling with Direct Strip Casting

This project offers an exciting opportunity to work at the forefront of sustainable metallurgy, directly addressing critical challenges in aluminium recycling and green manufacturing. The outcomes will contribute to a more circular economy by enabling high-quality, recycled aluminium alloys for structural applications in the automotive sector.

The successful candidate will play a key role in advancing the next generation of sustainable aluminium alloys by integrating fundamental materials research with industrially relevant processing technologies.

Aluminium production from raw ore is highly energyintensive, contributing significantly to global CO₂ emissions. Recycling aluminium requires 95% less energy than primary production and is essential for achieving net-zero emissions targets. However, with each recycling cycle, impurity levels—particularly Fe and Si—accumulate, leading to the formation;of coarse intermetallic particles (IMPs) that degrade mechanical properties, reduce formability, and compromise corrosion resistance. This challenge is especially pronounced in 5xxx-series aluminium alloys, which have seen rising impurity levels over the past decade. There are currently no efficient manufacturing solutions to mitigate the detrimental effects of these impurities, limiting the potential of high-recycled-content aluminium alloys.

This project will develop innovative alloying strategies and use non-equilibrium processing to tame impurity-related issues in 5xxx-series alloys. Direct Strip Casting (DSC), an emerging technology with the ability to refine microstructures through extreme cooling rates exceeding 10,000 °C/s, offers a promising;approach to manage impurities. Rapid solidification via DSC not only refines IMPs but also enhances impurity solubility in the as-cast condition,presenting a breakthrough for aluminium recycling. While 5xxx-series alloys possess an excellent balance of mechanical properties and corrosion resistance, their susceptibility to plastic instabilities limits their use to non-visible automotive components. This restriction complicates the dismantling;and sorting of aluminium at the end of a vehicle’s life, reducing recycling efficiency. Scandium (Sc) additions have shown promise in mitigating plastic instabilities and improving surface quality, but their use is limited by the inherently low solubility of scandium in aluminium.

This project will take advantage of the extreme cooling rates in DSC to increase scandium solubility and design a new class of high-performance aluminium alloys that can be broadly adopted in the automotive sector. The project will employ state-of-the-art characterization techniques to assess the impact of DSC processing;and scandium alloying. High-resolution transmission electron microscopy (HRTEM) and atom probe tomography (APT) will be used to quantify impurity distributions and analyse IMP populations. Mechanical performance, ductility, and formability will be evaluated using a GOM optical measurement system designed for Digital Image Correlation (DIC), enabling detailed analysis of deformation and strain paths.