A. Bongiovanni 1 *, M. Da Silva 2 , A. Castellero1
1 Department of Chemistry, NIS, University of Turin, Turin, Italy 2 Eurecat, Centre Tecnològic de Catalunya, Cerdanyola del Vallès, Spain
*andrea.bongiovanni@unito.it, manel.dasilva@eurecat.org, alberto.castellero@unito.it
Abstract
The automotive industry is working towards further reducing the carbon footprint of its vehicles and, with the electric vehicle transition, the raw materials used for the car itself need to be decarbonized.
Aluminium alloys offer infinitely recyclability, but they are sensitive to the Fe embrittlement that derives from recycling. High-pressure die casting AlSi10MnMg alloy is the most used alloy for structural components and is typically primary quality due to the high performances required.
The present study investigates the behavior of structural secondary AlSi10MnMg alloy developed in the SALEMA European project. The alloy is designed at the upper tolerance level of EN 1706 43500 alloy with 70% and 90% end-of-life recycle content.
This study analyzes the microstructure and casting defects, corrosion behavior and mechanical properties (bending and hardness tests) between as cast and T6 heat treatment. The microstructure and hardness are like the ones of primary alloys.
Tab 1. Chemical composition measured by Optical Emission Spectroscopy (OES), Sludge Factor (SF) and recycle content (%).
KEYWORDS
secondary aluminium alloy, high pressure die casting, AlSi10MnMg, T6, heat treatment, automotive, structural
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