Arc-Assisted Laser Welding Brazing of Aluminum to Steel

Abstract

Using laser beam as main heat source, and trailing arc as an assisted role, aluminum alloy was joined to galvanized steel in a butt configuration. Under suitable welding parameters, a sound welding seam was obtained. The interface intermetallic compounds layer and wetting behavior of weld joint were studied. The assisted arc can improve the wetting and spreading ability of weld pool duo to large temperature field. There are two different types of IMCs: near to the steel side one is Fe2Al5 with tooth-like shape and near to the weld seam side is the other one Fe4Al13 with flocculent-like shape. The highest tensile strength can reach 163 MPa when the fracture occurred at the weld seam.

Dissimilar Metal Welding

“…This special issue of Metals covers sixteen articles [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] focused on dissimilar metal joining techniques. Some of the published reports have confirmed the increasing interest in solid state welding processes, in particular friction based welding [6][7][8][9][10] and electromagnetic pulse welding [11,12], due to benefits related to the properties and achievable microstructure, and to energy and environmental considerations.…”

“…Some of the published reports have confirmed the increasing interest in solid state welding processes, in particular friction based welding [6][7][8][9][10] and electromagnetic pulse welding [11,12], due to benefits related to the properties and achievable microstructure, and to energy and environmental considerations. Other papers dealt with fusion welding techniques, mainly laser based [13][14][15][16], among others [5,17], and brazing processes [18,19]. Most of the applications are related to the automotive and aerospace sector, nevertheless dissimilar joints, characterized by improved fracture resistance, were indicated as an indispensable part of nuclear power plants for connecting the safe end (austenitic stainless steel 316L) to the pipe-nozzle (ferrite low-alloy steel A508) [20].…”

“…The Ag16.5CuZnSn-2Ga-0.15Ce brazed joint showed optimum performance compared to the other joints. Yu et al proposed the method of welding/brazing to realise a high quality welding of dissimilar metals, using 5A06 aluminium and galvanized steel welding using laser beam as the main heat source, and a trailing arc in an assisting role [19]. Under suitable welding parameters, a sound welding seam was obtained.…”

“…The highest tensile strength was observed to be 163 MPa, which was nearly 74% 5A06 aluminium alloy when the fracture occurred at the weld seam. Near the aluminium welding brazing seam, two different IMC formations appeared [19].…”

A Review on Laser-Assisted Joining of Aluminium Alloys to Other Metals

“…The mechanical properties of the IMC layer are mainly dependent of the composition and thickness, which are highly dependent on heat input. It is known that >10 µm IMC thickness is harmful for mechanical properties in the case of steel to Al welding [5]; being too thin may lead to poor bonding strength [6,7] (see Figure 1d). Therefore, the heat input must be lower and strictly controlled; the choice of the welding process (arc, laser beam, and resistance) can significantly determine the quality of the joint.…”