In this master’s thesis, we investigated the influence of the input material and punching conditions on the cut quality in the process of punching electrical sheet metal. In the theoretical part, we touched the entire punching process and the properties of several electrical sheet metal. In the experimental part, we measured the mechanical properties of selected electrical sheet metal. We designed a dedicated punching tool with different guiding inserts, which provided varying clearance gaps. The tool was mounted on a tensile testing machine, and we measured the forces generated when cutting different pieces of electrical sheet metal, using different machine speeds and clearances between the punch and the die. The lamellas were also produced on an automatic press in the production environment. Lamellas obtained under different punching conditions were analyzed under a microscope. We found that our measured mechanical properties corresponded to those provided by the manufacturers. We also determined that there is a direct relationship between the material hardness and the maximum force reached during punching. The cutting force decreases with increasing punching speed, while the quality of the cut edge improves. Increasing the clearance gap, however, leads to a decrease in the quality of the cutting edge.
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