Experimental Studies on Mechanical Behavior of TIG and Friction Stir Welded AA5083 -AA7075 Dissimilar Aluminum Alloys

Abstract

Welding is a suitable and better process to manufacture complex objects for aerospace, naval, and automotive structures. Service conditions and complexity in load acting force the manufactures to make joints between dissimilar materials. Thus, there is a need for efficient welding techniques to form sound joints and an understanding of imperfections and their effects. In this study an attempt has been made to study the joining feasibility of dissimilar aluminum alloys by two different welding techniques, namely, tungsten inert gas welding (TIG) and friction stir welding (FSW). Dissimilar AA5083-O and AA7075-T651 aluminum alloys successfully joined by considered welding techniques. Metallurgical and mechanical characteristics of fabricated weld joints are studied at different weld currents (80–120 amp) for TIG and various rotational speeds (800, 1000, 1100, 1200, and 1400 rpm) with constant traverse speed for FSW. Weld joints made by FSW exhibit superior tensile strength, whereas the joint line microhardness of TIG samples is higher than the FSW ones.