Advanced Approach to Modify Friction Stir Spot Welding Process

Nowadays, friction stir spot welding (FSSW) is used in automotive, rail vehicle construction, the aerospace industry, and electrical industry. In the current research, a modified version of the FSSW process entitled friction stir spot vibration welding was introduced to join Al5083 specimens. The joining specimens were vibrated normal to the tool movement direction, while the joint position cooled by passing coolant through the fixture. Different characteristics of developed joint namely microstructure, mechanical properties, corrosion behavior were studied. The results showed that stir zone grain size decreased significantly as the vibration was employed and the joint position was cooled. It was found that vibration enhanced the dynamic recrystallization and coolant decreased the grain growth. Both led to enhanced grain refinement in the stir zone. The results also indicated that shear strength and hardness of the weld region increased as the modified version of FSSW was applied. Corrosion tests revealed that corrosion resistance increased as the modified method was applied.