Weldability analysis of AA6061 and AA5082 using friction stir welding.

Welding of two dissimilar alloys of aluminium such as AA5082 and AA6061 using friction stir welding (FSW) and their weldability has been studied in terms of microstructural and mechanical characteristics of the formed joint. Assessment of tensile strength of the weld joint and microhardness in the weld zone and the thermo-mechanically affected zone were done. The joint showed a tensile strength of 0.253 kN/mm² and a Rockwell hardness of 54 HRA. Optical microscopy was conducted to study microstructure in different areas on the joined workpieces. Neither cracking nor porosity was observed in the weld zone in several high-resolution optical examinations, implying that defect free zones seem to have formed with the process parameters used, i.e. at 1000 RPM and 30 mm/min. This indicates a very good compatibility in welding the two alloys. [ABSTRACT FROM AUTHOR]