Mechanical Characterization of Dissimilar Friction Stir Welded Aluminium Alloys

Aluminium alloys have gathered wide acceptance in the fabrication of light weight structure requiring a high strength to weight ratio and good corrosion resistance modern structural concept demand reduction in both the weight as well as the cost of the production and fabrication of the material. This project work present non destructive evaluation and corrosion studies of dissimilar alloys which are widely used in marine, automotive, aircraft and aerospace industries. Compare with fusion welding processes, friction stir welding process is a solid state joining process is suitable for joining these two alloys. Dissimilar friction stir welded joints are fabricated by varying the process parameters rotational speed, welding speed with the taper cylindrical threaded profile tool keeping axial load and tilt angle constant. The mechanical properties tensile strength, impact strength and hardness of the dissimilar friction stir welded specimens were tested and compared with the base metals. All the joints fractured in the heat affected zone side of 6061 alloy side correspond to the minimum values in micro hardness profiles and it is observed that the weld parameters have a significant effect on mechanical and micro structural properties of the welds.