:: Artigo completo: https://doi.org/10.1007/s00170-025-16477-9
Abstract
This study presents a comprehensive experimental investigation of the three-electrode gas tungsten arc welding process (TE-GTAW) in autogenous mode, focusing on arc morphology, electrode thermal analysis, and weld quality in carbon steel plates. Keeping the total current constant at 300 A, configurations with one, two, and three electrodes were compared under different travel speeds. Arc images and voltage oscillograms revealed that increasing the number of electrodes enhances arc stability and vertical confinement, completely eliminating the humping defect at speeds up to 1.5 m/min. Two-color pyrometry measurements showed a significant reduction, up to 38%, in the maximum electrode temperature with the addition of arcs. Macroscopic analyses indicated reduced penetration and dilution with more electrodes, due to the broader thermal distribution of the coupled arc. Electromagnetic interactions between adjacent arcs, governed by Lorentz force and the Biot–Savart law, induce vertical elongation of the arc and concentrate energy in the central region. Despite the promising results, the technique requires advanced torch design and precise current control. Thus, the findings position TE-GTAW as a technically viable solution in the field of arc welding.
Keywords: TE-GTAW; Multicathode TIG; Coupled arc;Two-color pyrometry; Arc morphology; Humping mitigation
Referência:
DA ROSA, A. F.; SCHWEDERSKY, M. B.; SOUZA, M.; VIVIANI, A. B.; SILVA, R. H. G.. Coupled triple arc morphology and high-speed welding performance in the TE-GTAW process. Int J Adv Manuf Technol 140, 4127–4137 (2025). https://doi.org/10.1007/s00170-025-16477-9