A Materials and Mechanical Characterization of Friction Stir Welded Aluminum-Steel Joints with Respect to Intermetallic Compounds Content

Abstract:

In order to weld dissimilar materials with dramatically different properties such as aluminum and steel, friction stir welding (FSW) offers many advantages over conventional fusion welding techniques. However, producing strong and durable FSW joints requires full characterization of these joints including metallurgical and mechanical characterization. In this work, many process parameters and two different tools are put to test and the resulting FSW joints are characterized. Their mechanical strength is investigated in tension with respect to intermetallic compounds content analyzed using SEM coupled to EDX. The soundest 2mm thick joints recovered 55% of the strength of the original un-welded metal whereas in the case of the 3mm thick joints 47% of the strength could only be recovered in the best case. It was revealed that as the content in intermetallic compound increases the strength of the joints decreases. Additionally, it was found that the higher the mechanical deformation, the more these compounds are abundant; in other words, intermetallic compounds were largely found in the middle and bottom sections of the 3mm thick samples which is where the threads of the pin do most of their work. The compositions of these intermetallic phases along the abutting surfaces is also proposed based on the elemental composition of Fe and Al as detected by the scanning electron microscopy.

• Periodical: Key Engineering Materials (Volume 878)
• Pages: 104-112
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.878.104
• Online since: March 2021
• Authors: Zeina G. El Chlouk*, Mutasem A. Shehadeh, Ramsey Hamade
• Keywords: Dissimilar Joint, Friction Stir Welding, Intermetallic Compound, Tensile Strength

References

[1] DAWES, C. J., Friction Stir Joining of Aluminium Alloys, Bulletin. 6 (1995). http://ci.nii.ac.jp/naid/10006401749/en/ (accessed February 13, 2020).

[2] W.M. Thomas, E.D. Nicholas, J.C. Needham, M.G. Murch, P. Templesmith, C.J. Dawes, Friction Stir Welding, PCT/GB92/02203-No. 9125978.8., (1991).

[3] Z.G. El Chlouk, G. Ayoub, G.T. Kridli, R.F. Hamade, Intermetallic compound formation in Al/Mg friction stir welded (FSW) butt joints, in: ASME Int. Mech. Eng. Congr. Expo. Proc., 2014. https://doi.org/10.1115/IMECE2014-37213.

DOI: 10.1115/imece2014-37213

[4] V.C. Shunmugasamy, B. Mansoor, G. Ayoub, R. Hamade, Friction Stir Welding of Low-Carbon AISI 1006 Steel: Room and High-Temperature Mechanical Properties, J. Mater. Eng. Perform. 27 (2018) 1673–1684. https://doi.org/10.1007/s11665-018-3280-3.

DOI: 10.1007/s11665-018-3280-3

[5] X. Liu, S. Lan, J. Ni, Analysis of process parameters effects on friction stir welding of dissimilar aluminum alloy to advanced high strength steel, Mater. Des. 59 (2014) 50–62. https://doi.org/10.1016/j.matdes.2014.02.003.

DOI: 10.1016/j.matdes.2014.02.003

[6] H. Uzun, C. Dalle Donne, A. Argagnotto, T. Ghidini, C. Gambaro, Friction stir welding of dissimilar Al 6013-T4 To X5CrNi18-10 stainless steel, Mater. Des. 26 (2005) 41–46. https://doi.org/10.1016/j.matdes.2004.04.002.

DOI: 10.1016/j.matdes.2004.04.002

[7] M.M. Atabaki, M. Nikodinovski, P. Chenier, R. Kovacevic, UNCLASSIFIED: Distribution Statement A. Approved for public release Welding of aluminum alloys to steels: an overview, (n.d.).

DOI: 10.1515/jmsp-2014-0007

[8] T. Tanaka, T. Morishige, T. Hirata, Comprehensive analysis of joint strength for dissimilar friction stir welds of mild steel to aluminum alloys, Scr. Mater. 61 (2009) 756–759. https://doi.org/10.1016/j.scriptamat.2009.06.022.

DOI: 10.1016/j.scriptamat.2009.06.022

[9] C.M. Chen, R. Kovacevic, Joining of Al 6061 alloy to AISI 1018 steel by combined effects of fusion and solid state welding, Int. J. Mach. Tools Manuf. 44 (2004) 1205–1214. https://doi.org/10.1016/j.ijmachtools.2004.03.011.

DOI: 10.1016/j.ijmachtools.2004.03.011

[10] K. Kimapong, T. Watanabe, Friction stir welding of aluminum alloy to steel, Weld. J. (Miami, Fla). 83 (2004) 277–282.

[11] W. Liu, J. Ma, M. Mazar Atabaki, R. Kovacevic, Joining of advanced high-strength steel to AA 6061 alloy by using Fe/Al structural transition joint, Mater. Des. 68 (2015) 146–157. https://doi.org/10.1016/j.matdes.2014.12.028.

DOI: 10.1016/j.matdes.2014.12.028

[12] S. Rajakumar, C. Muralidharan, V. Balasubramanian, Influence of friction stir welding process and tool parameters on strength properties of AA7075-T6 aluminium alloy joints, Mater. Des. 32 (2011) 535–549. https://doi.org/10.1016/j.matdes.2010.08.025.

DOI: 10.1016/j.matdes.2010.08.025

[13] Z.G. El Chlouk, H.H. Achdjian, G. Ayoub, G.T. Kridli, R.F. Hamade, The effect of tool geometry on material mixing during friction stir welding (FSW) of magnesium AZ31B welds, in: Proc. TMS Middle East - Mediterr. Mater. Congr. Energy Infrastruct. Syst. MEMA 2015, (2015).

DOI: 10.1002/9781119090427.ch23

[14] C. Blignault, D.G. Hattingh, M.N. James, Optimizing Friction Stir welding via statistical design of tool geometry and process parameters, J. Mater. Eng. Perform. 21 (2012) 927–935. https://doi.org/10.1007/s11665-011-9984-2.

DOI: 10.1007/s11665-011-9984-2

[15] P. Motalleb-nejad, T. Saeid, A. Heidarzadeh, K. Darzi, M. Ashjari, Effect of tool pin profile on microstructure and mechanical properties of friction stir welded AZ31B magnesium alloy, Mater. Des. 59 (2014) 221–226. https://doi.org/10.1016/j.matdes.2014.02.068.

DOI: 10.1016/j.matdes.2014.02.068

[16] L. Long, G. Chen, S. Zhang, T. Liu, Q. Shi, Finite-element analysis of the tool tilt angle effect on the formation of friction stir welds, J. Manuf. Process. 30 (2017) 562–569. https://doi.org/10.1016/j.jmapro.2017.10.023.

DOI: 10.1016/j.jmapro.2017.10.023

[17] Efunda, Efunda: The ultimate online reference for engineers, (n.d.). www.efunda.com.