Numerical Investigation on Using of Stationary Shoulder in Friction Stir Spot Welding of Al6061 Alloy

Friction stir spot welding (FSSW) is a solid-state joining method which is used widely for aluminum alloys. Stationary shoulder friction stir welding (SSFSW) is a modified friction stir welding (FSW) process to control the heat input in the nugget. In this study, a finite elementmodel was developed, and a stationary shoulder was implemented in friction stir spot welding of Al 6061 alloy. Then the temperature development, the size of heat affected zone (HAZ), and the material flow were compared with conventional FSSW. The results indicatethat the pick temperature is lower, and the heat affected zone is smaller in stationary shoulder FSSW while there is no significant change in the material flow. Also, the pick strain in the case of FSSW is about 25% more than SFSSW. In the case of FSSW, there is an expansion inmaterials due to the process condition which is eliminated when the shoulder makes contact with the plate surface

Keywords:

Friction Stir Spot Welding , Stationary Shoulder , Finite Element , Heat Affected Zone , Al6061