ENHANCEMENT MECHANICAL PROPERTIES OF VERTICAL COMPENSATION FRICTION STIR WELDED JOINTS, THROUGH CHANGING POST-WELD HEAT-TREATMENT CONDITIONS

Frictional stir welding (FSW) technology is increasingly used to weld various alloys, especially aluminum alloys, which are used in the manufacture of aircraft, ships, trains, etc. One of the most common techniques used to improve the mechanical properties of welded joints made of different alloy aluminum is the Vertical Compensation Friction Stir Welding (VCFSW) technique. Moreover, the use of different conditions of post-weld heat treatment of VCFSWed joints has a major impact on the mechanical properties of welded joints . Therefore, in the present work, different conditions of post-weld heat treatments were carried out on the VCFSW joints in order to improve the mechanical properties. Specifically, this paper focused on the effect of aging conditions (artificial aging at 120°C, 140°C, and 160°C) and 3 mm wide VCFSW static tape on mechanical properties such as fine hardness and tensile stress . Overall, the results indicated improvement in mechanical properties after using post-weld heat treatment. Specifically, the highest values of exact hardness and tensile strength were obtained at 140 °C, which is due to the change of the microstructure of the welded area by post-weld heat treatment conditions .