The recent rapid advances in digital inverter-based welding power sources have allowed the realization of pulse gas metal arc welding, which can achieve stable metal transfer even at low welding current and thus reduce heat input to the base material. Moreover, a tandem-wire process using two electrodes can dramatically increase welding productivity. In such a process, two pulse power sources are synchronized and the interference between the adjacent welding arcs is minimized. In this study, high deposition rate pulse welding for Al 5083 alloy was implemented by using Al 5183 wire of three different diameters-1.6, 2.4, and 3.2 mm. Unlike the single-wire process, tandem-wire welding was only implemented using 1.6-mm-diameter wire. The bead shape, deposition rate, process windows, and stability were evaluated for each process. The results indicate that large wire diameters and the tandem process are preferable for high deposition rates, and the penetration depth is dependent on the welding current and speed. The tandem process achieves a remarkably high deposition rate, but spatter generation at high-current levels needs to be addressed.
KeywordsGas metal arc welding, pulse welding, high deposition welding, Al 5083 alloy, thick plate, tandem, aluminum, pulsed gas metal arc welding, tandem gas metal arc welding, metal inert gas Date
High-deposition-rate welding is used in the fabrication of liquefied natural gas tanks from thick aluminium plates because the weld defect generally increases and the productivity decreases with increasing number of passes. In this study, high-deposition-rate gas metal arc welding was implemented in vertical-up and horizontal positions. High deposition was achieved in the vertical-up position by pulse welding using 2.4-mm single wire and 1.6-mm twin wires and in the horizontal position by electromagnetic lifting of the weld pool. The arc stabilities for the applied processes were examined and welding procedures for thick plates were developed. A total of 14 welding passes were required for the vertical-up welding of a 70-mm thick plate by using the conventional 1.6-mm single-wire process, and the fully penetrated welds could be achieved with 8 welding passes by using twin-wire welding. Also, 10 welding passes were required for the horizontal welding of a 35-mm-thick plate by the conventional approach, and 6-pass full-penetration welding was successfully implemented by applying an external electromagnetic field.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.