Recent Developments in Cladding and Coating Using Cold Metal Transfer Technology

One of the modern welding techniques for joining dissimilar as well as similar materials is cold metal transfer (CMT). Thanks to low heat input in the process, no-spatter welding is guaranteed. Regulated metal deposition in CMT improves the aesthetics of the weld bead. This review article critically analyzes CMT cladding techniques, cladding types and applications. Several combinations of base metal and cladding material have been covered in detail with particular emphasis to microstructure and mechanical properties. CMT cladding has made it feasible to clad steel and aluminum satisfactorily. It surpasses several cladding techniques as per literature. In fact, CMT cladding is an efficient additive manufacturing technology and finds application in the automotive, defense and power plants sectors. There are several issues worth researching in cladding and coating by CMT for enhancing the overall sustainability of the processes. Based on the limited experimental data in the literature, some empirical expressions are established between performance and process parameters. Particularly, it is noted that dilution in cladding is a linear function of heat input. There is enough scope to carry out physics-based modeling and extensive experimentation for verifying the empirical relations and update them. Modeling and simulation can supplement experimental research effectively.