Influence of Friction Stir Welding Parameters on the Microstructural and Mechanical Properties of Aluminium Alloy 6061

摘要

Aluminium Alloy 6061(A1-Mg-Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to-weight ratio and good corrosion resistance. Fusion welding of aluminum alloys posses certain problems like porosity, distortion due to high thermal conductivity and solidification shrinkage. Compared to the fusion welding processes that are routinely used for joining Aluminium alloys, Friction Stir Welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. In the present work an attempt is made to study the feasibility of joining Aluminium alloy 6061 by FSW technique. Tool Rotation Speed, Welding Speed and Axial Force play a significant role in the assessment of mechanical properties. Experiment has been carried out and twenty-seven joints have been made on 6061 AL alloy of same nature and tested for its tensile properties. The results were analyzed using ANOVA technique and optimum parameters were determined. The microstructure analysis has also been carried out for finding grain size at three weld zones namely Weld Nugget (WN), Thermo Mechanically Affected Zone (TMAZ) and Heat Affected Zone (HAZ) and observed the grain size.