Fe–Al intermetallic suppression of dissimilar RSW joints using stainless-steel interlayers

Abstract

Austenitic and ferritic stainless-steel interlayers for resistance spot welding of an AlSi-coated 2000MPa UTS press-hardened boron steel and a 6022-T4 aluminium alloy were investigated to improve joint performance. CALPHAD and kinetic-based simulations were explored to determine the effects of Cr on the formation of Fe-Al intermetallic compounds. Selected area diffraction reveals the formation of FeCrAl 9 along the interlayer-Al interface and suppresses the formation of FeAl 3 . The implementation of stainless-steel interlayers significantly improved the mechanical performance of the joint, with the 430 foil condition experiencing a substantial decrease in the Fe-Al intermetallic.

Dissimilar Joining of High-Strength Steel and Aluminum Alloy Using Resistance Spot Welding with Die- and Punch-Shaped Electrodes

“…Therefore, the combination of steel and aluminum alloys, i.e., the technique for joining dissimilar materials, is being developed. Methods using resistance spot welding [1][2][3][4][5][6], FSSW [7], laser welding [8], and mechanical fastening [9] have been considered for joining dissimilar materials such as steel and aluminum alloys. However, from the viewpoints of productivity and cost, it is desired to realize joining of dissimilar materials of steel and aluminum alloys using resistance spot welding.…”