Improved iron-tolerance in recycled aluminum alloys via direct strip casting process

TL;DR

This study demonstrates that direct strip casting refines microstructure and improves iron tolerance in recycled aluminum alloys, enabling better performance and sustainability in aluminum recycling processes.

Contribution

The paper introduces a detailed microstructural analysis showing that direct strip casting enhances iron tolerance by preventing coarse Fe-rich intermetallics in recycled aluminum alloys.

Findings

Alloys produced by direct strip casting have refined microstructures.

Fe is retained mainly in solid solution in DSC alloys.

Strip casting significantly improves Fe-tolerance in aluminum alloys.

Abstract

Recycled aluminum alloys are pivotal for sustainable manufacturing, offering strength, durability, and environmental advantages. However, the presence of iron (Fe) impurities poses a major challenge, undermining their properties and recyclability. Conventional manufacturing processes result in coarse Fe-rich intermetallic compounds that limit the tolerance of Fe content and negatively influence performance of advanced aluminum alloys. To address this, rapid solidification techniques like direct strip casting have been explored. In this work, a detailed study of the strip cast microstructure was conducted by scanning electron microscopy, electron backscattered diffraction and atom probe tomography. Our results reveal that alloys produced by DSC exhibit significantly refined microstructures and are free from coarse Fe-rich intermetallics, thereby retaining the majority of Fe in solid solution. These findings indicate that strip casting significantly enhances Fe-tolerance in aluminum alloys, making it an attractive process for future aluminum recycling, with implications for sustainable high-performance applications.