Resistance spot welding of steel and aluminium sheet using insert metal sheet

Abstract

The present paper reports the resistance spot welding of steel and aluminium sheets using aluminium clad steel sheets as insert metals. Intermetallic compound layers were formed in the weld zones in direct spot welding of steel sheets to aluminium sheets. Thus, the strength of these joints was lower than that of aluminium to aluminium joints. Intermetallic compound layers were also formed at the steel/aluminium interfaces of the insert metal in welding of steel to aluminium using an insert metal sheet. However, the strength of these joints was of the same order as that of the aluminium joints. The fracture mode of these joints varied with the welding current. The suitable welding current for steel to aluminium joints varied between the values suitable for steel to steel and aluminium to aluminium joints. The fatigue strength of joints using insert metals was somewhat lower than that of the aluminium joints.

Joining of dissimilar materials

“…Oikawa et al [181] showed slightly thicker IMC (Fe 2 Al 5 ) layer thickness with an Al-steel clad transition material versus direct Al-steel welding, approximately 5 versus 2 mm, respectively, but a better mechanical performance with the clad material. They attributed this to differences in fracture mode in part due to geometrical differences related to the insertion of the clad material.…”

“…It can easily be automated, is very flexible, and since the weld gun electrodes are clamped, small gaps between the sheets can be levelled. A number of researchers have applied RSW to dissimilar Al-steel joints [91,163,181,191,232,257,267,297], as well as material combinations including Mg-steel [138], glasssteel [78], Cu-Ni plated steel [178], stainless steel-Ti [253], Ti-Al [193], and Al-Mg [90,106]. The benefits of enabling the RSW of Alsteel would be the re-use of existing infrastructure to join both like and dissimilar material combinations and the significant cost avoidance necessary to retool for a new joining process.…”

“…Another method to impact the heat imbalance between the Al and steel is through manipulation of electrode materials or geometries. There is limited information published, though most welding Al directly to steel use a matching pair of F-type rounded electrodes with dome radius 40 mm and a face diameter of 6 mm [55,181,256,257]. Truncated, 458 cone with a 8 mm face diameter has also been noted [166].…”

Resistance spot welding of dissimilar alloys 1008 low carbon steel5052 aluminum alloy

“…In the 1990s, the aluminum panels began to be used in car body due to the environmental issue and weight reduction (Carle & Blount, 1999) (Barnes & Pashby, 2000) (Sakurai, 2008) (Oikawa, Ohmiya, Yoshimura, & Saitoh, 1999). Among many aluminum alloys, the automotive industry is used the 5XXX and 6XXX Al-alloys.…”

Effects of Shielding Gas Flow Rate and Power Waveform on Nd:YAG Laser Welding of A5754-O Aluminum Alloy

“…Compared with GMAW and GTAW, laser welding has the advantage of a substantially higher welding speed, even under heavily reduced thermal loads. Moreover, in contrast to the resistance spot welding of aluminum sheets, in which the stable surface oxide layer leads to process instabilities and produces rapid electrode wear, [7][8][9][10] the laser beam interaction is free of contact with the workpiece, and hence offers a higher production reliability and significant quality improvements. Furthermore, laser welding has a low heat input and is highly versatile.…”