Exploring the cutting edge: Recent trends in cold metal transfer welding

Cold metal transfer welding is known for its automated welding process, which is equipped with shortcircuit-based deposition of filler wire, which allows it to control its heat input parameter properly along with a wire feed rate. Cold metal transfer’s main characteristic, which greatly affected the manufacturing industries, is joining thin, similar, or dissimilar metal sheets as the processing heat input is minimal. This review paper (covering 104 studies) examines how joining different metals with varying welding parameters affects their weld appearance, microstructure, tensile strength, and the formation of joint failure. The main focus was on what additional methods, like hardfacing or post-heat treatment of material, must be adopted to enhance the joint's weld quality and appearance. The paper starts with the investigation of numerous dissimilar weld joints formed by the cold metal transfer technique, along with the effect of varying welding parameters and ultrasonic-assisted cold metal transfer hybrid welding on the weld quality and post–pre-weld heat treatment of materials. A comparison of different cold metal transfer arc modes employed in wire-arc additive manufacturing has also been discussed briefly. At the end of the analysis, it was noted that some metal joints had a positive impact, and some gained a negative effect while increasing the heat input. The research articles studied in this paper indicate that not every material would exhibit the same welding property when subjected to a specific set of varying welding parameters.