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Effect of Process Parameters on the Strength of Swept Friction Stir Spot Welded Plates

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Abstract

Swept friction stir spot welding, a derivative of friction stir welding is a solid-state process for joining materials by using frictional heat generated due to rotating tool along the weld line. The main objective of this study is to investigate the strength of the swept friction stir spot welded aluminum plate by changing the welding process parameters. In this paper, the joining was done on thin aluminum alloy plates using the Octaspot™ tool path with a radius of 10 mm. The samples were welded using a CNC milling machine. The study focuses on two process parameters which are the tool rotational speed and the welding traverse speed. The samples were analyzed on their shear strength and the results show that the higher the tool speed, the higher the shear strength is. However, when the rotational speed is increased, the shear strength shows a decreased pattern. The overall results are in good agreement with other published results.

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... They reported that SFSSW is able to produce the mechanical properties similar to riveting. Awang et al. [22] investigated the SFSSW of aluminium alloy and reported that tool travel speed and heat dissipation are significant parameters influencing the strength of the weld joint. Yoon et al. [23] conducted the welding with a new approach similar to SFSSW process for joining Al/Fe dissimilar metals. ...
... As shown in Eq. (22), Pareto optimal solution set obtained are considered to be more uniformly distributed if S has a smaller value. The ideal value of S is equal to zero because this implies all solution members of F 1 are equidistant from one another. ...
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