Studies on effect of parameters of Friction Stir Welded MgAl alloys and characterization

Abstract

quotDuring this cutting-edge technology time, the industrial need is driven by the higher efficiency and performance at low cost. Aluminum alloy has 2.7 g/cc density and demonstrates high strength to density ratio, high creep and corrosion resistance, high electrical and thermal conductivity, good workability, excellent appearance, and better recyclability. Magnesium alloy has 1.7 g/cc density and shows higher strength to density ratio, excellent damping capabilities, casting, forming, and recycling characteristics. The attractive properties of both these light metals motivate engineers to fabricate the hybrid structure. The industries such as automobile, aerospace, railway, shipbuilding and marine have shown a shift towards applications of metals like aluminum and magnesium which is reflected in increased production. newlineFabrication of hybrid structures with welding is challenging due to different properties of materials. Dissimilar Al/Mg welding presents a challenge due to limited solubility and the formation of detrimental intermetallic compounds (IMC). The IMC formation issue can be addressed by adopting a low temperature generating welding process or manipulating IMC variety and distribution, or controlling reaction time and energy. Conventional fusion welding technology suffers a drawback since it is associated with coarse grain structure and defects like crack, porosity, inclusion, lack of penetration, lack of fusion etc. due to melting and solidification of metals. To overcome this issue low temperature generating process of solid-state welding like Friction Stir Welding (FSW) is a good choice. Dissimilar Al/Mg welding using FSW limit the formation of detrimental IMC. newlineTo further improve dissimilar Al/Mg FSW joint properties, weld modification techniques or post-weld processing techniques may be employed. There is not much information available for dissimilar Al/Mg joint property improvement by the approaches mentioned earlier. The present research work presents two different approaches, weld modification of FSW