Processing Parameters and Microstructure of 6mm 6061 Aluminum Alloy Joints by Friction Stir Welding

Abstract:

The processing parameters of friction stir welding for 6061 aluminum alloy were optimized by using the orthogonal experimental design in the range analysis and variance analysis with the tensile strength and elongation as the parameters. The results show that the stirring speed is the key factor, even welding speed, pressure and stirring head working angle also influence welding quality. The highest tensile strength can reach to 251MPa as the elongation reached to 7.5% with the optimum parameters of rotating speed of 800r/min, welding speed of 200~220mm/min, pressure volume of 0.4mm and stirring head working angle of 3°. The weld nugget zone (NZ) is composed of uniform fine equiaxed grains, while thermo mechanically affected zone (TMAZ) is composed of slender coarse grains. The structure of heat affected zone (HAZ) is developed along the deformation direction with the effect of thermal cycle.The fracture morphology of the FSW joints shows ductile dimple features which validates the high ductility of the joint during the tensile testing.

• Periodical: Key Engineering Materials (Volume 739)
• Pages: 50-55
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.739.50
• Online since: June 2017
• Authors: Yang Jia*, Ke Hong Wang
• Keywords: Alluminum Alloy, Friction Stir Welding, Mechanical Properties, Microstructure, Processing Parameters

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