Determination of weldability study on mechanical properties of dissimilar Al-alloys using Friction stir welding process

Abstract

Abstract Friction stir welding is a solid-state joining process, which is used for joining the two materials in numerous critical application and much other commercial importance. The Aluminum alloys AA2024 and AA7075, which are heat-treatable alloys, it is widely used in aerospace, automotive and transportation industries. The aluminum alloys exhibit greater strength, good impact, superior hardness, excellent corrosion resistance, improve fatigue resistance and lesser density. The current investigation aims at joining of the dissimilar material of AA2024 and AA7075 Al-alloys by the effect of different welding parameters. The tool rotational speed was varied between 1000 rpm and 1400 rpm, welding speed between 20 mm/min and 40 mm/min and axial force of 4KN is kept at constant. The microstructure examination was performed using Scanning electron microscopy (SEM) and the mechanical properties were evaluated through the tensile test. The microstructure examination result displays the appearance of coarsening grains, when there the rotational speed is increased as a reason of more heat input and occurrence of dynamic recrystallization in the deformed zone. Furthermore, the tensile strength is increasing with a decrease in welding speed of Friction stir process (20 m/min & 1000 rpm). The corrosion properties (salt spray) test illustrates that no type of corrosion occurs in all the friction stir samples for the exposure period of 48 h.