Microstructure and Mechanical Properties of A6061/GA980 Resistance Spot Weld

Abstract:

Resistance spot welding was performed on steel and an Al alloy to investigate the microstructural and mechanical properties of the joint. An Al-Mg-Si aluminum alloy A6061 and an alloyed zinc-plated steel sheet GA980 were used as specimens. Resistance spot welding was performed at welding currents of 16 kA, 20 kA, and 22 kA, welding time of 0.24 s, and welding pressure of 5 kN. To investigate the strength of the welds, the tensile shear test and the cross tension test were conducted, and the fatigue test was also conducted. The nugget diameter increased with an increase in the welding current. The tensile shear strength and cross tension strength increased with the increase in the welding current. In the tensile shear fatigue test, interface fracture was observed in the low cycle fatigue region. In the cross tension fatigue test, it was confirmed that the higher the welding current, the better the fatigue properties in the low-cycle fatigue region.

• Periodical: Key Engineering Materials (Volume 966)
• Pages: 25-30
• DOI: https://doi.org/10.4028/p-rUe1Zd
• Online since: November 2023
• Authors: Toshiki Nonomura*, Tsuyoshi Kosaka, Tatsuya Kobayashi, Ikuo Shohji, Muneyoshi Iyota
• Keywords: Alloyed Zinc-Plated Steel Sheet, Aluminum Alloys, Resistance Spot Welding

References

[1] Y. Hirata, Welding and joining technology in government project of research and development on innovative structural materials operated by NEDO and ISMA, Journal of The Japan Welding Society 86 (2017) 6-11.

DOI: 10.2207/jjws.86.6

[2] K. Martinsen, S. J. Hu, B. E. Carlson, Joining of dissimilar materials, CIRP Ann. Manuf. Technol. 64 (2015) 679-699.

DOI: 10.1016/j.cirp.2015.05.006

[3] H. M. Rao, J. Kang, L. Shi, D. R. Sigler, B. E. Carlson, Effect of specimen configuration on fatigue properties of dissimilar aluminum to steel resistance spot welds, Int. J. Fatigue 116 (2018) 13-21.

DOI: 10.1016/j.ijfatigue.2018.06.009

[4] T. Matsuda, K. Owada, A. Numata, H. Shoji, T. Sano, M. Ohata, A. Hirose, Influence of interfacial structure on the fracture behavior of friction stir spot welded dissimilar joints, Mater. Sci. Eng. A 772 (2020) 138743.

DOI: 10.1016/j.msea.2019.138743

[5] K. Kumamoto, T. Kosaka, T. Kobayashi, I. Shohji, Y. Kamakoshi, Microstructure and Fatigue Behaviors of Dissimilar A6061/Galvannealed Steel Joints Fabricated by Friction Stir Spot Welding, Materials 14 (2021) 3877.

DOI: 10.3390/ma14143877

[6] T. Ogura, A. Hirose, Microstructural control of interface and mechanical properties in dissimilar metal joining between aluminum alloy and steel, J. Jpn. Inst. Light Met. 66 (2016) 503-511.

DOI: 10.2464/jilm.66.503

[7] K. Kumamoto, I. Shohji, T. Kobayashi, M. Iyota, Effect of microstructure on joint strength of Fe/Al resistance spot welding for multi-material components, Mater. Sci. Forum 1016 (2021) 774-779.

DOI: 10.4028/www.scientific.net/msf.1016.774