Mechanism of Porosity Suppression in GMAW-GTAW hybrid welding process of AA5083 aluminium alloy

AA5083 aluminium alloy is widely used in most frequently as a structural material for manufacturing lightweight aircraft, cars, and high-pressure containers in order to improve energy efficiency. However, the traditional welding technique of aluminium alloy has not satisfied the industrial demand because of poor welding quality. One of the major problems in welding aluminium allots is porosity formation in weld metal, causing the reduction in their mechanical properties and usages. Therefore, the aim of this research is to study the oxide cleaning action of a hybrid welding process that combines Gas Tungsten Arc Welding which has the ability to clean oxide surfaces and Gas Metal Arc Welding which has a high deposition rate. Welded samples of aluminium alloy AA5083 are evaluated by using microstructure analysis and inspected by radiographic testing to determine weld quality and the amount of porosity. A high-speed camera also analyzes metal transfer patterns and oxide cleaning actions. The effect of the dual cleaning action of GMAW and GTAW has strongly influenced the oxide cleaning behavior. Meanwhile, the heat from GTAW arc plasma can be remelted to the GMAW weld metal surface, allowing porosities to move out of the weld surface. It can demonstrate that the GMAW – GTAW hybrid welding process can remarkably reduce the porosity in the weld metal of aluminium alloy AA5083