In the aviation industry, aluminium alloys are often used, mainly because of their favorable strength to mass ratio. Friction stir welding (FSW) is slowly replacing classic rivet joining, because of better mechanical properties of joints, elimination of notching effect and easier construction. However, this joining also has some disadvantages. During the welding process, heat is generated, which leads to changes in the microstructure and the introduction of tensile residual stresses, which is also reflected in the lower corrosion resistance. In the thesis we analyzed electrochemical corrosion properties and residual stresses of high strength Al alloys series 2017A-T451 and 7075-T651 coupled with FSW welding using different welding parameters. From the point of view of the analyses of the effects of welding, residual stresses in the base materials and in the weld joint were measured. The measurement was performed three times, i.e. before and after the abrasive water jet cut and after electrochemical measurements. This enabled the full insight of the effect of the specific procedure. Various electrochemical methods have been used for corrosion resistance analysis in an aggressive chloride environment. It has been found that smaller tensile residual stresses in the weld are generated during the welding process using higher rotaion per feed (RPF) ratio. At the same time, the electro-chemical methods confirmed the best corrosion resistance of the weld joint, in the mixing zone with extremely fine, equiaxed grains. Open circuit potential measurements have confirmed the noblest corrosion potential with 2017A-T451 alloy, whereas the specimen taken from the FSW weld exhibited the best corrosion resistance with the highest polarization resistance and passivation and repassivation ability.
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