On Additive Manufactured AlSi10Mg to Wrought AA6060-T6: Characterisation of Optimal- and High-Energy Magnetic Pulse Welding Conditions

Abstract

This novel research aims to examine the macro and microstructural bonding region development during magnetic pulse welding (MPW) of dissimilar additive manufactured (AM) laser powder-bed fusion (L-PBF) AlSi10Mg rod and AA6060-T6 wrought tube, using both optimal- and high-energy welding conditions. For that purpose, various joint characterisation methods were applied. It is demonstrated that high-quality hermetic welds are achievable with adjusted MPW process parameters. The macroscale analysis has shown that the joint interfaces are deformed to a waveform shape; the interface is starting relatively planar, with waves forming and growing in the welding direction. The observed thickening of the flyer’s wall after welding is the result of its diametral inward deformation, taking place during the process. A slight increase in microhardness was adjacent to the faying interfaces; a higher increase was measured on the AlSi10Mg material side, while a smaller one was observed on the AA6060 side. Along the wavy interfaces, resolidified “pockets” of material or occasionally discontinuous short layers exhibiting different morphologies, were detected. The jet residues are typically located towards the end of the weld, confirming a temperature rise that exceeds the melting temperature of both alloys. Far from the weld zone, extremely thin-film deposits were clearly observed on the inner flyer surfaces. The formation of isolated Si particles and thin-film deposits may point out that the local increase in temperatures leads to melting or even evaporation vaporisation of superficial layers from the colliding parts. It is worth noting that this type of jet residue was discovered for the first time in the present research. The current research work is expected to provide an understanding of weld formation mechanisms of additively manufactured parts to conventional wrought parts conforming to existing wrought/wrought weld knowledge.

Probing Magnetic Pulse Welding of Thin-Walled Tubes

“…2020, 4, x FOR PEER REVIEW 2 of 19 [2,3]. The consolidation between the two parts occurs without any bulk melting [4], although local melting at scattered locations along the joint interface is reported for MPW of AA6060 flyer tubes and copper target rods [5], AA1050 flyer and target sheets [6] and AA6060 flyer tubes and AlSi10Mg target rods [7]. For the overlapping assembly, the outer part is referred to as the flyer and the inner part is referred to as the target.…”

Microstructure and Joint Strength of Magnetic Pulse Welded Aluminum/Aluminum-Coated Steel Joint

“…23) Furthermore, dissimilar Al alloy joints have also the sinusoidal wavy interface. 4,24,25) In this study, since welding of A1050 and Alcoated steel was performed, the metals which sandwich the welding interface are A1050 and Al coating (AlSi alloy). Therefore, formation of the sinusoidal wavy interface was expected but it appears that the ridge parts of the interface were crushed (Fig.…”

Analytical Estimation of Electromagnetic Pressure, Flyer Impact Velocity, and Welded Joint Length in Magnetic Pulse Welding

“…An advance estimate of the EM pressure and the flyer impact velocity is required to design a suitable process schedule and to assess the joint quality in MPW [2]. The use of comprehensive numerical models [3] and wide-ranging experiments [4] is growing, to improve the insightful understanding of MPW, but these are computationally intensive [5] and time-consuming [6]. A practical framework is needed for a fast and reliable estimate of the EM pressure, flyer impact velocity, and the joint dimensions for a given process schedule to enhance the commercial application of MPW [7].…”