Effect of friction stir welding (FSW) process parameters on dissimilar aluminium alloys: An overview.

In this work, the process parameters of friction stir welded dissimilar joints of aluminium alloys were analysed. The experimental investigations are carried out by the various researchers are evaluated and tabulated. Friction Stir Welding (FSW) is a solid-state metal joining process. Solid state metal joining means, the metal is not melted during the welding process and also original metal characteristics remain unchanged. Selection of material with specific properties is the key parameter in many industrial applications, especially in the aircraft and automotive industries. However, processing of such alloys with specific properties, like high strength, suffer from certain limitations in terms of cost and time of production, apart from the reduction in ductility. High strength accompanied by high ductility is possible with materials having fine and homogenous grain structures. Hence there arises a necessity to develop a processing technique that would produce a material with small grain size that satisfies the requirements of strength and ductility as well as the cost and time of production. FSP expands the innovation of friction stir welding (FSW) developed by The Welding Institute (TWI) of United Kingdom in 1991 to develop local and surface properties at selected locations. FSP is a new and unique thermo mechanical processing technique that alters the microstructural and mechanical properties of the material in a single pass to achieve maximum performance with low production cost in less time. In the present work, FSP is investigated as a potential processing technique for aluminum alloys because of various advantages it offers over other processes as mentioned above. This FSW process mostly implemented on aluminium alloys. FSW of dissimilar alloys are controlled by various process parameters, in this paper, the effect of FSW tool geometry is analyzed and tabulated. From this brief discussion, we can improve the quality of FSW process. [ABSTRACT FROM AUTHOR]