Weld bead characteristics in pulsed GMA welding of Al-Mg alloys

The object of this investigation was to determine a suitable pulse parameter combination to obtain good-quality welds for a given weld bead size. Weld bead characteristics have been influenced by the parameters of pulsed current, i.e., peak current (I-p), peak duration (T-p), background current (I-B) and background duration (T-B) The effect of pulsed current parameters on gas metal are (CMA) weld bead geometry was studied, and a single diagram in the nondimensional form was developed, representing many aspects of weld bead characteristics, This diagram was then used to select the most suitable combination of GMAW-P parameters for a given weld bead size in the welding of a 6-mm (0.236-in.) thick AA 5083 Al-Mg alloy base metal using 1.2-mm (0.047 in.) diameter ER 5356 filler metal. The correlation of the cross-sectional area of penetration, total -cross-sectional area of weld and nondimensional width of weld bead with operating parameter 'n' (a nondimensional heat input rate that gov- erns the dimension of the weld pool) was obtained. Nondimensional terms were used to plot the results for all materials and welding variables on a single diagram, with many aspects of plate fusion behavior represented on a single graph.