Influence of Axial Force on Tensile Strength and Microstructural Characteristics of Friction Stir Buttwelded Aluminum Alloy/Steel Joints
In this work, the effect of axial force on the tensile strength, microhardness, joint interface microstructure and fracture surface morphology of friction stir welded (FSW) dissimilar butt joints of 3 mm thick aluminum (Al) alloy AA5052-H32 and HSLA steel IRS-M42-97 were investigated. The FSW trials were carried out by varying the axial force from 5–9 kN while keeping the other parameters constant. The highest joint strength of about 90% of the ultimate tensile strength (UTS) of the base Al alloy is obtained at 7 kN axial force. It is found that axial force in the range, 6–8 kN could produce joints with joint strength above 75% of the UTS of the base Al alloy. EDS and XRD analysis suggests that the intermetallic compound (IMC) layer formed at the joint interface is consistent with FeAl3 and FeAl at lower and higher axial forces, respectively. Joint interface analysis shows that the thickness of IMC layer formed at the interface is critical in the performance of the joint and the joint with an average IMC layer thickness of about 1 μm at the joint interface has exhibited the highest joint strength.
Keywordswelding friction stir welding dissimilar butt joint microstructure tensile strength axial force
- 12.K. Kimapong and T. Watanabe, “Friction stir welding of aluminum alloy to steel,” Weld. J., 83, No. 10, 277–282 (2004).Google Scholar
- 23.M. Yýlmaz, M. Çöl, and M. Acet, “Interface properties of aluminum/steel friction welded components,” Mater. Charact., 49, No. 5, 79–86 (2002).Google Scholar
- 24.M. Rathod and M. Kutsuna, “Joining of aluminum alloy 5052 and low carbon steel by laser roll welding,” Weld. J., 83, No. 1, 16–26 (2004).Google Scholar
- 28.L. N. Larikov, Diffusion, in: J. H. Westbrook and R. L. Fleischer (Eds.), Intermetallic Compounds. Principles and Practice, Vol. 1: Principles, John Wiley & Sons, Chichester (1995), pp. 757–770.Google Scholar