In the final assignment, we analysed the MAG welding process of 60 mm thick stainless-steel sheet 1.4404 in the X-butt weld with a gas mixture of 97.5% argon and 2.5% carbon dioxide. To approve the welding process, it was necessary to carry out an inspection of the welded joints on the weld. In the theoretical part, the characteristics of stainless steels, basic concepts of welding, typical defects and investigation or control of welded joints were first presented. During welding, the root wool was first produced with the help of a ceramic ferrule, followed by the filling welds. A total of 33 welds were made. The main challenge was to keep the weld temperature between passes below 110 °C during welding. If this temperature was exceeded, the weld had to be cooled. After welding, we conducted non-destructive and destructive testing. The quality of the welded joint was verified by penetrating test and radiographic control. Tensile strength test, bending test, Charpy impact test and metallographic examination were performed on welded joints. We found that the selected and developed welding process ensures the production of high-quality welded joints on thick sheets. This also confirms the approval of the welding procedure used.
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