The effect of chloride fluxes of AZ۶۱ magnesium alloy welded byActivated Tungsten Inert Gas Welding (A-TIG)

This study comprehensively investigated the effect of chloride fluxes, i.e., FeCl۳, MgCl۲, andNaCl, on Tungsten Inert Gas (TIG) welding of AZ۶۱ magnesium alloy. These fluxes were used toenhance weld properties, and their effects on weld microstructure and hardness were examined. Thewelding process was carried out at a current intensity of ۱۲۰ A. The appearance and cross-sectionalgeometry of the welds were carefully analyzed under each condition and compared with the without flux.Microstructural examinations using optical microscopy (OM) and scanning electron microscopy (SEM)were conducted to study the effect of active fluxes on metallurgical characteristics of the welds in thefusion zone (FZ). X-ray diffraction (XRD) was used to determine the phases in the welded samples,revealing a similarity in phase structure between the weld region of all samples and the base metal AZ۶۱.Vickers hardness tests using a ۱۰۰ g force showed that the flux application did not significantly impacthardness, with the hardness of the flux-applied welds almost identical to that of the without flux. Visualinspection of the welds revealed that using chloride fluxes resulted in molten metal spattering and poorweld bead appearance. FeCl۳ provided the best results among the fluxes used, showing ۲.۷ times greaterpenetration depth than without flux. Microstructural examinations indicated that the fusion zone structurefor all samples, despite differences in the applied fluxes, was similar to the without flux. The resultssuggest that the A-TIG method using active chloride fluxes can enhance efficiency and penetration depthof AZ۶۱ magnesium alloy welding without having a negative impact on the final structure and hardnessof the weld.