Effect of Shot Peening on Submerged Friction Stir Welded AA 6061 T6 Alloy under Various Cooling Media

Author(s): Kowsalya G, Bhuvaneshwari A and Arunkumar N

The aim of this investigation to study the effect of shot peening on the mechanical and microstructural properties of submerged friction welded joints of Al 6061 T6 under three different cooling mediums .Submerged Friction Stir Welding was carried out under various cooling media like water, brine solution, coolant oil by keeping other parameters like rotational speed (1000 rpm), welding speed (60mm/min) constant. The optimum parameter combinations for maximizing the yield strength ,tensile strength and percentage of elongation were identified in the previous research by Senthil kumar et al. (2016) .The optimum condition of the medium, rotational speed, welding speed were found to be coolant oil,1000 rpm,60 mm/min, respectively. Two samples from each cooling media can be welded at constant welding parameters and subjected to metal cutting process for further shot peening process. The shot peening was carried out on the one friction stir welded sample from each cooling condition (water, brine solution, coolant oil) using a steel balls of diameter (6mm), rotational speed (750rpm) and for 45 min. Tensile test, Vickers hardness test , Microstructure evaluation was carried out on the respective weld peened and weld unpeened joints. In added to that the effect of cooling media of welded joints on the mechanical properties, microstructural properties were discussed. Finally the comparison has to be made between the properties of weld peened and weld unpeened of Al 6061 T6 alloy.