Investigation of RSW process on three-layer joining of steel to 6061-T8 aluminum

ABSTRACT

In this article, the RSW process (Resistance Spot Welding) on 6061-T8 aluminum alloy was studied. Spot resistance welding of two-layer plates is difficult and has very low mechanical properties. That is why this process is not practical for industrial applications. In this paper, a spot welding method was used with a novel three-layer technique, which means that an aluminum sheet was located between two sheets of steel and RSW was performed. The effects of RSW parameters including both current and welding time were investigated on the diameter of nugget, the microstructure of heat-affected zone and reaction layer, and mechanical properties. The results show that this method increases the tensile shear load compared with two-layer joining. Also, increasing of welding current, both tensile shear load and weld nugget diameter increased first, and then reduced. The interfacial reaction layer and weld heat-affected zone (HAZ) consisted of $FeA{l}_3$, $FeA{l}_{2}andF{e}_{2}A{l}_5$.

KEYWORDS:

• RSW
• process
• interfacial
• welding
• layer
• 6061
• aluminum
• tensile
• HAZ
• steel

Acknowledgments

We would like to express our gratitude from Golpayegan University of Technology.