GMA welding investigations on the effect of alternating shielding gases on bead profile characteristics of AA6061 aluminum alloy

The bead profile geometry of aluminum alloy has been taken for investigation and the influence of alternate gases in the gas metal arc welding (GMAW) process. In the GMAW process, welding currents of 105 A, 120 A, 135 A, and 150 A are considered for evaluating the weld parameters. Further, the influence of various alternating duration of argon (Ar) and helium (He) shielding gases on the GMAW process has been investigated. Consequently, the alternating duration between shielding gases is used as 0.25 s (He) and 0.75 s (Ar), 0.5 s (He) and 0.5 s (Ar), and pure argon for joining the AA6061 alloy plates. It is found that the 0.5 s (Ar) and 0.5 s (He) shielding gases promoted fewer porosity effects compared with other alternating shielding gas and pure argon. Also, the microhardness and depth of penetration were significantly improved in 0.5 s (Ar) and 0.5 s (He) compared with 0.75 s (Ar) and 0.25 s (He) and pure argon shielding gas. The welded surface morphological study has been conducted for further evaluation of welding currents and shielding gas effects in the GMAW process.