Residual stress measurement in the friction stir welded of Al-6061-T6 and Al-7075-T6 using contour method

The friction stir welding process (FSW) is a solid state of welding processes. Thermal and mechanical residual stresses in the weld and zone close to it is produced due to local temperature and its restraints depends on the yield strength of the base metal. Because of theinfluence of residual stresses on mechanical properties in friction stir welding is required to assess these stresses. In this study, residual stress distribution and mechanical properties of dissimilar 7075-T6 and 6061- T6 aluminum alloy plates after friction stir weldingprocess was studied by the contour method. For this operation, friction stir welding process has been studied in two states. The results showed that the residual stress is the tensile type in the weld line. Also, the distribution curve of residual stresses indicates that theresidual stress type in the center of the sample was tensile and in the edges are compressive and the residual stress is 21% of the yield strength of the base metal.

Keywords:

friction stir welding , residual stress , contour method , aluminum alloy.