Aluminium alloy EN AW-6082 is characterized by high strength, excellent corrosion resistance and good weldability, which makes the products of the mentioned alloy widely applicable in the transport and construction industries. Globalization and market dynamics dictate the time chain from the client to the supplier, which strives for high performance and quality, whose product depends on the ejection and optimization of work. In the master's thesis, the influence of the deformation rate on the length of the press residue during the hot extrusion process of the aluminium alloy EN AW-6082 was discussed. The test was carried out by extruding a bar with a diameter of 80 mm, at an average speed of ram movement of 9 mm⠙s-1, 9.5 mm⠙s-1, 10 mm⠙s-1, 10.16 mm⠙s-1 and 11 mm⠙s-1. The results of the mechanical tests showed deviations of the mechanical properties of the beginning and end of the extruded bars. While the mechanical properties of the rod end approach the nominal values, the influence of defects is initially too high, which is reflected in the lower strength properties. Metallographic analysis confirmed the presence of inhomogeneous mixing of the material and the content of oxide inclusions of different sizes at the places with the lowest mechanical properties. The experimental part was supported by computer simulations of extrusion using the finite element method, where the temperature development, material flow and deformation rate were monitored at all five different extrusion speeds. The results of simulations and metallographic analysis showed the influence of ram movement speed on the direction of the material flow, temperature profile and the length of the reach of internal defects.
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