Mechanical and micro structural behaviour of flux coated GTAW and FSW joined AA6061 aluminium alloy

Abstract

In the present paper, an attempt was made to experimentally investigate the mechanical properties of flux coated weld butt Joints of AA6061 aluminium alloy by considering two different welding processes namely GTAW and FSW. Gas Tungsten arc welding (GTAW) is preferred due to its comparatively simpler applicability and better economy. And the revolutionary solid-state welding technique, friction stir welding (FSW) is used due to its defect-free welds with good mechanical properties. Rolled plates of 3 mm thickness have been used as the base material for preparing single pass butt welded joints. The filler metal used to join the plates is AA4043 aluminium alloy. In this the investigation, tensile properties, Micro hardness, Microstructure and fracture surface morphology of the GTAW and FSW joints have been evaluated and the findings are contrasted. FSW Joint of Aluminium alloy AA6061 has shown superior mechanical properties compared to the GTAW Joint, this is mainly due to the formation of very fine, fully equally axed grain microstructures in the weld zone.