Achieving a circular economy increasingly places the aluminium industry at the forefront, resulting in more and more research focusing on the possibilities and impacts of recycling aluminium alloys. By understanding the influence of the secondary aluminium content on individual properties of aluminium alloys, we gain insight into the "limits" where such alloys can be applied or where their altered properties will not suffice. In this master's thesis, research was conducted on profiles from the 6xxx series alloy, specifically the EN AW 6060 alloy. We compared the microstructural, mechanical and corrosion properties of the alloy, where the input material consisted of nearly 70 % of secondary material, with the alloy that was made with the input composition, containing 70 % of primary aluminium. For both alloys, we calculated the carbon footprint and found that in the case of using 70 % secondary material, the carbon footprint of the alloy was almost three times lower. Chemical analysis showed a higher content of impurities – iron, in the alloy with an increased secondary content, and a higher magnesium content. The alloy with the increased secondary fraction also exhibited slightly higher strength properties and consequently poorer elongation at fracture. Bending and crash properties remained almost unaffected, while the increase in the secondary fraction did not affect the thermal stability of the alloy. Regarding the corrosion resistance of the alloy, increasing the secondary content had a somewhat negative impact. It slightly deteriorated, as the increase in iron in the alloy is directly related to the rate of intergranular corrosion. With the increase in iron, there is an increase in sites where oxygen and hydrogen reactions occur, leading to a correspondingly higher rate of corrosion.
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