Abstract: This article presents prediction of ultimate tensile strength of joint between aluminium alloys AA6101 and AA6082 by using of underwater friction stirs welding (UWFSW). The considered process parameters are tool rotational speed, tool linear feed and tool shoulder diameter. The change of tool shoulder diameter and other parameters tensile strength varies. The ultimate tensile strength may increase or decrease with increase of tool rotation speed. Also, can decrease with increase of tool shoulder diameter and tool linear speed. Here, tensile strength of the welded alloy of the process, were measured and examined. It has been examined in this experiment that maximum tensile strength of joint is achieved 217 N/mm2 by applying 18mm shoulder diameter with a rotational speed of 1000 rpm & welding speed of 30 mm/min. The tensile strength of welded specimens reached in the UWFSW joint is 75-80% of the parent metal tensile strength. Underwater friction stir welding is more efficient and decent welding technique compare to the other welding categories.

Keywords: Dissimilar material, H13 tool, Process parameter, tensile strength, Underwater friction stir welding.

| DOI: 10.17148/IARJSET.2021.8680