Influence of Tool Pin Profile in Underwater Friction Stir Welding of Aluminium 6061 Alloy

Abstract

Light metals like Aluminium and Magnesium are usually joined by welding processes like Friction Stir Welding (FSW). Aluminium being light weighted is used in various aeronautical applications. During welding using FSW, the Heat affected zone (HAZ) obtained is very much high due to direct exposure of air. In order to minimise the heat affected zone and also to improve the Weld strength, an attempt has been made to weld Aluminium Al 6061 alloy using Underwater Friction stir welding (UFSW). By carrying out the FSW process underwater, the hardness of the welded structures is also increased due to rapid cooling. In this present study, the effect of different pin profiles like cylindrical, square and conical profiles on the welded specimen is studied. Consequently, the mechanical properties of these welded specimens are also compared and analysed.

A Comparative Study on Fatigue Response of Aluminum Alloy Friction Stir Welded Joints at Various Post-Processing and Treatments

“…FSW structures are often subjected to severe repetitive loadings in service, causing abrupt failure due to the fatigue phenomenon. In an attempt to improve the fatigue resistance of friction stir welded joints, researchers have proposed several techniques including adding nano/micro particles to the weld nugget to create a local metal matrix composites (MMCs) [4][5][6][7], optimizing welding process parameters [8][9][10][11][12] through tool shape and operation rate, introducing novel welding tools with different geometrical features [13][14][15][16][17], inducing compressive residual stresses by means of different methods of cold working [18][19][20][21][22][23], and weld joint post-heat treatment [24][25][26].…”

“…They reported higher tensile strength at a tool traverse speed of 400 mm/min as compared with that at 100 mm/min. Premkumar et al [9] and Babu et al [10] tested several FSW joints to propose an optimized set of welding process parameters to achieve better mechanical properties. Lombard et al [11] optimized FSW process parameters in order to achieve defect-free FSW joints of Al 5083-H321 alloy with highest tensile and fatigue strengths.…”