State-of-the-art of advanced gas metal arc welding processes: Dissimilar metal welding

The manufacturing industry has for many years shown interest in opportunities offered by the welding of dissimilar metals, for example, in transportation to reduce vehicles weight and in power plants, to fit heterogeneous working conditions. Early gas metal arc welding (GMAW) processes had limited control of heat input, but advanced GMAW processes of the last decades offer new perspectives for welding dissimilar metals. The study review briefly dissimilar metal welding (DMW) and investigates advanced GMAW processes with emphasis on their general operating principles and arc control. Experiments performed on dissimilar metals using GMAW processes are then reviewed, highlighting those made using advanced gas metal arc welding processes. The study collates data from scientific literature on fusion dissimilar metal welding, advanced gas metal arc welding processes and experiments conducted with conventional GMAW. The study shows that the welding procedure specification is an important factor in dissimilar metal welding. Advanced GMAW processes have significant potential in fusion welding of dissimilar metals in the case of ferrous metals, ferrous and non-ferrous metal combinations and non-ferrous metals of different grades. Accurate control of heat input allows more effective prediction of intermetallics and better control of post heat treatments. Increased understanding of advanced processes will permit development of more suitable specifications of gas metal arc welding procedures for dissimilar metal welding. Process flexibility and adaptability to robotic mass production will allow for wider application of this process and the avoidance of costly alternative methods.