Mechanical Properties of Gas Metal Arc and Friction Stir AA6082-T6 Weldments

Abstract

The general purpose of the presents report is to determine the mechanical properties of AA6082-T6 subsequent to gas metal arc welding (GMAW) and friction stir welding (FSW). Hardness testing have been carried out for the weldments. In addition, tensile and Charpy V-notch testing has been carried out for the unaffected base metal, the fusion/stir zone and the HAZ and HAZ/TMAZ zones, both transverse and longitudinal to the weld- ing/extrusion direction.It is concluded that HAZ softening is a major problem both in the GMA and the FS weld- ments. Still, the total width of the HAZ in the FS weldments is smaller compared to the GMA weldments. The total strength reduction for the GMA and the FS welds was 43 and 34%, respectively. The general observations is that the FS weldments show slightly better mechanical properties compared to the GMA weldments. This is further reflected in the calculations of load-bearing capacity of the joints, showing that the FS weldments exhibit the highest capacity under otherwise identical conditions due to the combined effect of a lower HAZ strength reduction and a smaller HAZ width.