Resistance spot welding of aluminium to steel with magnetic-assisted apparatus was performed for the first time to understand the metallurgical joining mechanism in the melt region and at the material interface. The electromagnetic force promoted circular motion of the molten metal and accelerated the diffusion of Fe atoms to the aluminium sheet, which induced finer grains, thinner intermetallic compound layers, reduced interface defects, and elevated hardness of the resulting aluminium nugget. Coach peel tests revealed that welds made with an external magnetic field presented enhanced strength and ductility compared to welds made with no external magnetic field. The enhanced strength and ductility resulted in a transition of the fracture behaviour from brittle interfacial mode to ductile button pullout mode, and increased the peak load and the energy absorption by 90% and 1327%, respectively.
TanakaT, MorishigeT, HirataT.Comprehensive analysis of joint strength for dissimilar friction stir welds of mild steel to aluminum alloys. Scripta Mater. 2009; 61:756–759.
2.
RestC, JacquesPJ, SimarA.On the joining of steel and aluminium by means of a new friction melt bonding process. Scripta Mater. 2014; 77:25–28.
3.
MartinsenK, HuSJ, CarlsonBE.Joining of dissimilar materials. CIRP Ann. 2015; 64:679–699.
4.
HuSQ, HaselhuhnAS, MaYW, Comparison on resistance spot weldability of AA5754/steel and 6022/steel. Weld J. 2020; 99:224s–238s.
5.
HuSQ, HaselhuhnAS, MaYW, Influencing mechanism of inherent aluminum oxide film on coach peel performance of baked Al-steel RSW. Mater Design. 2021; 197:109250.
6.
OikawaH, OhmiyaS, YoshimuraT, Resistance spot welding of steel and aluminium sheet using insert metal sheet. Sci Technol Weld Join. 1999; 4:80–88.
7.
SiglerDR, SchrothJG, KaragoulisMJ, New electrode weld face geometries for spot welding aluminum. Sheet Metal Welding Conference XIV. 2010.
QiL, LiFZ, ChenRM, Improve resistance spot weld quality of advanced high strength steels using bilateral external magnetic field. J Manuf Process. 2020; 52:270–280.
10.
ShenQ, LiYB, LinZQ, Effect of external constant magnetic field on weld nugget of resistance spot welded dual-phase steel DP590. IEEE T Magn. 2011; 47:4116–4119.
11.
YaoQ, LuoZ, LiY, Effect of electromagnetic stirring on the microstructures and mechanical properties of magnesium alloy resistance spot weld. Mater Design. 2014; 63:200–207.
12.
HuangM, ZhangQX, QiL, Effect of external magnetic field on resistance spot welding of aluminum alloy AA6061-T6. J Manuf Process. 2020; 50:456–466.
QiL, LiFZ, ZhangQX, Improvement of single-sided resistance spot welding of austenitic stainless steel using radial magnetic field. J Manuf Sci E. 2021; 143:1–11.
LiYB, LinZQ, HuSJ, Magnetohydrodynamic behaviors in a resistance spot weld nugget under different welding currents. Sci China Ser E Technol Sci. 2008; 51:1507–1515.
18.
LiYB, LinZQ, LaiXM, Induced electromagnetic stirring behavior in a resistance spot weld nugget. Sci China Technol Sci. 2010; 53:1271–1277.
19.
WanZX, WangHP, WangM, Numerical simulation of resistance spot welding of Al to zinc-coated steel with improved representation of contact interactions. Int J Heat Mass Tran. 2016; 101:749–763.
20.
LiY, LuoZ, YanFY, Effect of external magnetic field on resistance spot welds of aluminum alloy. Mater Design. 2014; 56:1025–1033.
21.
ChenNN, WangHP, CarlsonBE, Fracture mechanisms of Al/steel resistance spot welds in coach peel and cross tension testing. J Mater Process Technol. 2018; 252:348–361.
22.
SiglerDR, CarlsonBE.Impediments to developing resistance spot welding processes for joining aluminum to steel. Conference proceedings AWS Sheet Metal Welding Conference XVIII. 2018.
23.
SunDQ, ZhangYY, LiuYJ, Microstructures and mechanical properties of resistance spot welded joints of 16Mn steel and 6063-T6 aluminum alloy with different electrodes. Mater Design. 2016; 109:596–608.
24.
BouayadA, GeromettaC, BelkebirA, Kinetic interactions between solid iron and molten aluminium. Mat Sci Eng A. 2003; 363:53–61.
25.
SpringerH, KostkaaA, PaytonEJ, On the formation and growth of intermetallic phases during interdiffusion between low-carbon steel and aluminum alloys. Acta Mater. 2011; 59:1586–1600.
