Influence of weld process parameters on material characterization of friction stir welded joints of aluminium alloy AA۶۰۶۱-T۶

Abstract: Friction stir welding, a solid state innovative joining technique, is widely being used for joining aluminium alloys for aerospace, marine automotive and many other applications of commercial importance. FSW trials were carried out using a vertical machining centre (VMC) on AA۶۰۶۱ alloy. The main objective of the present work was to evaluate the weld processing parameter of friction stir weld (FSW) process for AA۶۰۶۱-T۶ alloy and to determine the properties of the obtained joints with respect of welding speed. Experiments have been conducted by varying the welding speed of ۵۵-۷۰ mm/min and the rotating speed was fixed at ۱۷۰۰rpm. Tensile properties, microstructure, microhardness, fractography, and corrosion resistance of FSW joints were investigated in this study. The result showed that  there was a variation of grain size  in each weld zone which depends upon the material and process parameters of FSW in the joint itself. The coarsest grain size was observed in heat affected zone (HAZ), followed by the thermomechanically affected zone(TMAZ) and the nugget zone(NZ). The maximum tensile strength of ۱۸۴MPa and highest joint efficiency of ۴۹.۳۲% was obtained on the joint fabricated at ۵۵mm/min of welding speed.