Effect of Tool Tilt on Formation of Tunnel in Friction Stir Welded 5083 Joints: An Experimental Study

Abstract

Friction stir welding (FSW) being a solid-state joining process is immune to the various defects faced in traditional fusion welding process. However, defects such as voids, joint line remnants and tunnel defects are common imperfections in FSW. In the present study, an attempt has been made to investigate the effect of tool tilt on the formation of tunnel defect, while keeping all other process parameters constant. Tool tilt is a significant parameter as it influences the flow patterns of the stir zone, frictional forces and the heat generated. The study has shown that the tool tilt can alter the flow of plasticized material in the stir zone and for that reason can control the quality of weld.