A study on the mechanical, electrochemical and microstructural behaviour of AA5052 welded sheets

Abstract

Aluminium 5xxx series alloys are most robust non-heat-treatable aluminium alloy and mostly used in aerospace, automotive components and body structures due to its high corrosion resistance, good strength and light weight. The alloy used in this work is AA5052 H32 (cold rolled) of 1 mm thickness to highlight the precedence of friction stir welding (FSW) over fusion welding technique, i.e., Tungsten Inert Gas welding (TIG). In TIG, the selected input variable parameter is welding speed and the other parameters such as inert gas flow rate, welding speed and frequency were kept constant during the study. In FSW, the selected input variable is feed rate, and the parameters such as plunge depth and tool rotational speed were kept constant after conducting several trials. Mechanical, Electrochemical, and Microstructural behaviour of both welded samples were studied. It was found that Friction stir welding samples has better mechanical properties than TIG welding due to solidification cracks and porosity defects. The tensile and microhardness results of FSW were 7.3 % and 5.4% more than TIG due to solidification cracks, porosity defects and intermetallics formed. The corrosion behaviour of both FSW and TIG were less than the base material due to precipitate dissolution. In the present study a comparative study of FSW and TIG is studied and reported.