The thesis presents the process of technological measures that make it possible to eliminate unwanted visual lines on the anodized surface of extruded profiles made of aluminum alloy EN AW 6060. In the introduction to the thesis, we learn about the problem of the visual quality of extruded profiles, which we are dealing with. In the theoretical part, the segments that we need to know and understand are presented, as they largely affect the surface quality of the extruded profiles. These are: the basics of aluminum alloys, the technological process of casting billets, the extrusion process and the influence of its parameters, the artificial aging process and anodization. In the experimental work, the aim was to determine whether visual lines appear on the surface of extruded profiles after anodization, if the mass fraction of iron w(Fe) in the chemical composition of aluminum alloy EN AW 6060 is increased to the upper limit of 0.3 %, which is determined by the standard. The profiles were extruded at different preheating temperatures of the billets, with the aim of finding out which combination leads to the most beautiful surface after anodization. Artificial aging was optimized for the best samples and, in addition to achieving the required mechanical properties, we also determined its effect on the appearance of visual lines on the anodized surface. Microstructure analyzes were carried out, which were analyzed and compared between the samples. It was found that the surface after anodization is of better quality with an alloy with a lower proportion of iron and a higher preheating temperature of the billet. Artificial aging also has a great influence on the presence of visual lines on the anodized surface, and the reason lies in the presence of Mg2Si and AlFeSi phases near the surface, which reduce conductivity and consequently destroy the quality of the anodizing coating.
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