Submerged friction stir welding of 6061-T6 aluminium alloy under different water heads

The aim of this paper is to determine the feasibility of submerged friction stir welding of 6061-T6 aluminium alloy on different water heads through macrostructuralanalysis.In this work, aluminium 6061-T6 alloy was friction stir welded under normal and submerged conditions at different rotational speeds of 400 rpm, 800 rpm, 1200 rpm, 1600 rpm. The water head was varied from 10 to 30 mm in the case of thesubmerged friction stir welding process. In both normal and submerged friction stir welding processes, a welding speed of 45 mm/min, a normal load of 30 kN, tool tilt angle of 2, depth of tool penetration and tool geometry were kept constant. Torque is measured during the welding process, and power (kW) is calculated after the welding process. The macrostructural analysis was carried out for locating defect formation and identifying the feasible working range of process parameters of the welded aluminium 6061-T6 alloy. The mechanical properties such as ultimate tensile strength and microhardness of submerged friction stir welded of 6061 aluminium alloys were investigated.Scanning Electron Microscope (SEM) metallography was used for comparing the microstructure of the parent material, friction stir welded and submerged stir welded samples. © 2018 Universidade Federal de Sao Carlos. All rights reserved.