Abstract—An experimental investigation has been carried out on Hardness distribution, tensile properties and microstructure of weld butt joints of 6061 aluminium alloy. Two different welding processes have been considered: an innovative solid state welding process known as friction stir welding (FSW) process and Gas welding. Hardness distribution results showed a general decay of mechanical properties of Gas joints, mainly due to high temperature experienced by the material. Instead, in FSW joint, lower temperatures are involved in the process due to severe plastic deformation induced by the tool motion and lower decay of mechanical properties. In the nugget zone a slight recovery of hardness is observed due to recrystallization of very fine grain structure. Hence from industrial perspectives, FSW process is very competitive as it saves energy, has higher tensile strength and prevents the joints from fusion related defects.

Index Terms—Friction stir welding, Gas welding, Hardness, Aluminum 6061

Cite: Kuncha Ramu and D Gopi Chandu, "Comparative Experimental Study of Friction Stir Welding and Gas Welding Process on AA6061," International Journal of Mechanical Engineering and Robotics Research, Vol.3, No.4, pp. 412-416, October 2014.