Lightweight automotive components based on nanodiamond-reinforced aluminium alloy: A technical and environmental evaluation

This study aims to evaluate the use of nanodiamonds (ND) as potential reinforcements to improve the mechanical properties of aluminium for use in high-quality automotive components. Additionally, the use of components manufactured from reinforced aluminium is assessed regarding environmental effects considering the life cycle of the component. To do this, a master alloy of aluminium/20 vol% ND was developed using mechanical alloying, which embedded and uniformly distributed non-agglomerated ND particles inside the aluminium matrix. Then, specimens of reinforced aluminium alloys containing 0.5 wt% ND were produced using a mixing system to manufacture the final automotive components. SEM images revealed even distributions of nanoparticles of <10 nm in size within the aluminium; synchrotron investigation revealed the diamond structures of the nanoparticles. The incorporation of the nanoparticles induced improvements in the yield stress and ultimate tensile strength, and a dramatic improvement of the ductility. Finally, the holistic life cycle analysis was conducted by the accepted Life Cycle Assessment (LCA) methodology. The results showed an environmental net balance of CO ₂ emissions after the automobile using ND-reinforced aluminium alloy components had reached ~33% of its useful lifetime, indicating a significant reduction in the environmental impact in the value chain of the component, especially considering 50% recyclability, as this provides environmental benefits compared to the life cycles of equivalent components produced from weightier materials like steel.