Quantitative analysis of surfaces of cross-section in butt welding of aluminum alloy 5083 using laser–arc hybrid welding

The alloy aluminum of 5000 series will have relatively high strength through solid solution strengthening of Mg. However, when laser welding the 5000 series aluminum alloys, the Mg is selectively evaporated by welding heat due to its low melting and vaporization points, resulting in a reduction in the strength of welds. Therefore, laser welding application is difficult because of such a reduction in strength[Formula: see text] [M. Peel, A. Steuwer, M. Preuss and P. J. Withers, Acta Mater. 51, 4791 (2003); A. Haboudou, P. Peyre, A. B. Vannes and G. Peix, Mater. Sci. Eng. A 363, 40 (2003)]. In this paper, welding experiments were carried out using laser and laser–arc hybrids on aluminum alloy 5083 with 8-mm thickness. Tensile testing, scanning electron microscopy (SEM) analysis and electron probe microanalyzer (EPMA) analysis were carried out on specimens on which the laser and laser–arc hybrid weldings were performed. According to the tensile test results, the tensile strength during laser–arc hybrid welding was greater than 85% of the parent metal. In addition, EPMA analysis showed that the strength of the laser–arc hybrid welds was maintained by supplementing the optional evaporating Mg element, since they use the filler wire.