Aluminum alloys are widely used in demanding engineering applications, as they are characterized by good corrosion resistance as well as mechanical and material properties. Development of new welding technologies enabled joining high-strength aluminium alloys, which are know to be difficult to weld by conventional fusion welding techniques. New technologies offer different researches of the impact that welding has on the mechanical properties of the weld joint and the surrounding material. In the final project paper, we therefore analyzed the transverse residual stresses in the joints of heterogeneous high-strength aluminum alloys 2017A-T451 and 7075-T651. The analysis was performed on six sample joints that were welded with different welding parameters using friction stir welding method. Further, we have selected measuring points in the transverse direction of the weld and then the residual stresses were measured at these points using the X-ray diffraction method.Based on the results of the measurements, we have plotted the residual stress distribution graphs. We have shown that they are, on the average, higher tensile residual stresses on the forward side of the weld. We have also found that bigger extremes of residual stresses are present on the retreating side of the weld in which the highest value was in sample 3 (RPF: 20 rot/cm) where the compressive residual stresses measured were -76,48± 22,46 MPa).
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