Friction stir welding of dissimilar alloy combinations—A Review

Abstract

Friction stir welding (FSW) is one among solid-state welding processes that can be employed for producing joints between dissimilar combinations with more ease than that of fusion welding processes. Several high coupled physical phenomena have addressed FSW as an extremely complex process. It is around three decades of invention, optimization of the parameters have been carried out even today by many researchers all over the world to obtain sound joints. This article focuses mainly on the research developments in the dissimilar FSW (DFSW), with the factors that are involved in joint fabrication between dissimilar materials. From the literature, it is found that the most influential factors in deciding the quality of the joints are pin profile, shoulder shape, welding speed and tool rotational speed. In addition, all other parameters will provide incremental support to it. The study on microstructure in different zones and the mechanical properties of welded specimens are elaborated from the available literature. Special attention is given to the reinforcement of micro- and nano- sized solid particles in the DFSW process. Future studies of DFSW are discussed based on the untracked studies that are not available in the literature.