Experimental Investigation of the Effect of Using Tools with Tapered Pins in Friction Stir Welding (FSW) of AA6061-T6 Aluminum Alloy
Subject Areas :Saleh Al Khatour 1 , Maziar Mahdipour Jalilian 2 , Mahdi Karami Khorramabadi 3
1 - Department of Mechanical Engineering, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran
2 - Department of Mechanical Engineering, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran
3 - Department of Mechanical Engineering, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran
Keywords: Friction Stir Welding (FSW), Tool Geometry, Tapered Pin, Aluminum Alloy, Strength of Weld,
Abstract :
The present study investigated the effect of using tools with tapered pins in Friction Stir Welding (FSW) of AA6061-T6 aluminum alloy. Two techniques named conventional FSW and Refill Friction Stir Welding (RFSW) were used for this purpose. Five tools with different tapered angles (0, 5, 10, 15, and 20 degrees) were used. To study the mechanical properties, tensile, three-point bending, and Vickers microhardness tests were performed. Macrographic and microstructural tests were also used to investigate the metallurgical properties of the welded samples. Based on the results, it was found that the key factors determining the ductility and strength of the welded specimens are the type of welding process (conventional FSW or RFSW) and the geometry of the tool pin (straight or tapered pin). Furthermore, it was found that all specimens welded by RFSW have higher tensile strength and elongation than the samples welded by conventional FSW.
[1] Hassanifard, S., Nabavi-Kivi, A., Ghiasvand, A. and Varvani-Farahani, A. 2021. Monotonic and fatigue response of heat-treated friction stir welded Al 6061-T6 joints: Testing and characterization. Materials Performance and Characterization. 10(1):353-369. doi.org/10.1520/MPC20200076.
[2] Li, J.Q. and Liu, H.J. 2013. Characteristics of the reverse dual-rotation friction stir welding conducted on 2219-T6 aluminum alloy. Materials & Design. 45:148-154. doi.org/10.1016/j.matdes.2012.08.068.
[3] Li, J.Q. and Liu, H.J. 2015. Effects of the reversely rotating assisted shoulder on microstructures during the reverse dual-rotation friction stir welding. Journal of Materials Science & Technology. 31(4):375-383. doi.org/10.1016/j.jmst.2014.07.020.
[4] Liu, H.J., Li, J.Q. and Duan, W.J. 2013. Research on reverse dual rotation friction stir welding process. In Proceedings of the 1st international joint symposium on joining and welding. Woodhead Publishing. doi.org/10.1533/978-1-78242-164-1.25.
[5] Shi, L., Wu, C.S. and Liu, H.J. 2015. The effect of the welding parameters and tool size on the thermal process and tool torque in reverse dual-rotation friction stir welding. International Journal of Machine Tools and Manufacture. 91:1-11. doi.org/10.1016/j.ijmachtools.2015.01.004.
[6] Thomas, W.M., Staines, D.J., Watts, E.R. and Norris, I.M. 2005. The simultaneous use of two or more friction stir welding tools. Abington, Cambridge, TWI.
[7] Liu, H.J. and Zhang, H.J. 2009. Repair welding process of friction stir welding groove defect. Transactions of Nonferrous Metals Society of China. 19(3):563-567. doi.org/10.1016/S1003-6326(08)60313-1.
[8] Kumari, K., Pal, S.K. and Singh, S.B. 2015. Friction stir welding by using counter-rotating twin tool. Journal of Materials Processing Technology, 215:132-141. doi.org/10.1016/j.jmatprotec.2014.07.031.
[9] Jain, R., Kumari, K., Pal, S.K. and Singh, S.B. 2018. Counter rotating twin-tool system in friction stir welding process: A simulation study. Journal of Materials Processing Technology. 255:121-128. doi.org/10.1016/j.jmatprotec.2017.11.043.
[10] Ghiasvand, A., Hassanifard, S., Jalilian, M.M. and Kheradmandan, H. 2021. Investigation of tool offset on mechanical properties of dissimilar AA6061-T6 and AA7075-T6 joint in parallel FSW process. Welding in the World. 65:441-450. doi.org/10.1007/s40194-020-01037-4.
[11] Gadakh, V.S. and Kumar, A. 2014. Friction stir welding window for AA6061-T6 aluminium alloy. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture. 228(9):1172-1181. doi.org/10.1177/0954405413510289.
[12] Hassanifard, S., Alipour, H., Ghiasvand, A. and Varvani-Farahani, A. 2021. Fatigue response of friction stir welded joints of Al 6061 in the absence and presence of inserted copper foils in the butt weld. Journal of Manufacturing Processes. 64:1-9. doi.org/10.1016/j.jmapro.2021.01.010.
[13] Callister Jr, W.D. and Rethwisch, D.G. 2020. Callister's Materials Science and Engineering. John Wiley & Sons.