Aluminium and its alloys rank among the most important structural materials in modern industry due to their low density, good corrosion resistance, and a wide range of mechanical properties that can be tailored through the selection of alloying elements and appropriate heat treatment. Among them is the EN AW 6082 alloy from the 6XXX series, whose primary alloying elements are magnesium and silicon, though additions of manganese, copper, chromium, or iron are also often present. Thanks to its favourable balance of strength, formability, good weldability, and the possibility of anodizing, this alloy is widely used in the automotive, aerospace, construction, and other industries.
An important step in the production of aluminium alloys is homogenization, as casting often results in chemical inhomogeneity and non-equilibrium microstructural constituents that impair mechanical properties and hinder further plastic deformation. Therefore, this thesis investigated the effect of homogenization temperature on the macro- and microstructure of the EN AW 6082 alloy, with special emphasis on surface changes. The experimental work included thermodynamic calculations followed by homogenization in the temperature range of 500–540 °C. Samples in both as-cast and homogenized states were analysed using differential scanning calorimetry (DSC) and metallographic examination.
The main objective of the research was to determine the influence of homogenization on the surface and to evaluate the parameters of properly conducted homogenization that enable achieving the optimal properties of the EN AW 6082 aluminium alloy. It was found that a lower homogenization temperature, e.g. 500 °C, is required to prevent surface oxidation, as the phenomenon was more intense at higher temperatures. The time after homogenization also proved to be an important parameter, since after 85 days an increased concentration of magnesium was detected on the surface.
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