Fundamental Experiments of Pulsed GMA Additive Manufacturing

Abstract

Metal 3D printing based on laser sintering is important in various industrial fields. However, its limitations are being revealed due to the need for expensive machines and metal powder. Meanwhile, wire arc additive manufacturing (WAAM) is rapidly arising as an alternative technology thanks to its relatively economic cost. Despite the boom of WAAM, its advantages are not that clear, because the majority of the research to date has been based on relatively expensive facilities, of which the cold metal transfer (CMT) machine is representative. In this study, the WAAM process is being improved with general pulsed GMA to lower the barrier of high cost and facilitate the adoption of the WAAM process in actual manufacturing industries. All process parameters, such as current, voltage, welding speed, and CTWD were examined to figure out a proper synergic line for WAAM. As a result, a high sulfur proportion wire and proper process parameters could be suggested. Finally, the proposed synergic line successfully produced a steel wall consisting of 10 layers with a thickness of 7.2 mm and a height of 22.4 mm, which can serve as an example of WAAM with pulsed GMA.