Mechanical Properties of AW-5083 Alloy Joints Welded By Hybrid Method – FSW and MIG

Abstract

Abstract The article presents the research results on the mechanical properties of aluminum alloy AW-5083 and its joints welded by hybrid method – traditional MIG and FSW. AW-5083 alloy is the most currently used in shipbuilding industry. Friction Stir Welding (FSW) – a new technology can be successfully used for butt-welding of different types of aluminum alloy sheets. FSW method can be an alternative to traditional arc welding methods i.e. MIG or TIG. Hybrid welding (FSW with MIG or TIG) could be used in cases when joining only by FSW is not possible. Welding parameters used for the connection of the sheets were presented. Metallographic analysis showed the correct construction of structural bonded joints. The research was carried out using a static tensile test in accordance with the requirements of the Standard PN-EN ISO 4136:2013-05. Flat samples cut perpendicular to the direction of rolling were used. The research was conducted at the temperature of +20ºC. The test shows that the mechanical properties of joints made by hybrid method compered to native material were lower. The tensile strength of joint was lower by 20% then native material 5083 while its yield stress was lower only about 6%. The biggest change was observed in case of plastic properties. Elongation of joint was over 50% lower compared to native material. Despite the decrease of mechanical properties, they meets the requirements of classification societies, so the conclusion is that hybrid method (FSW and MIG) of joining AW-5083 can be applied in shipbuilding industry.