Improved mechanical properties of laser-arc hybrid welded Al/steel dissimilar butt-joint through beam oscillation

Abstract

Al/steel butt-joints are hard to be fusion welded because of the easily formed and unevenly distributed brittle intermetallic compounds (IMCs) at the interface. Laser-arc hybrid welding was used to suppress the IMCs formation and improve its uniformity through beam oscillation. The weld defects of uneven formation and lack of fusion were suppressed at optimised frequency of 150 Hz. Furthermore, the interface was transferred from an uneven two-layer IMCs ( ≥ 3.8 µm), including Al 5 Fe 2 and Al1 3 Fe 4, to a uniform single-layer Al 5 Fe 2 ( ≤ 1.4 µm). Owing to these changes, not only the tensile property was increased by 65% compared to non-oscillating weld, but also the bending property that hardly reported in most studies was enhanced by 96%.

A Review: Laser Welding of Dissimilar Materials (Al/Fe, Al/Ti, Al/Cu)—Methods and Techniques, Microstructure and Properties

“…Analysis of 2021 publications shows that promising areas are modeling [ 101 , 102 ], the use of wobbling [ 103 , 104 , 105 ], bilateral laser welding [ 106 ], the application effect of preliminary preparation of the titanium surface on its wettability with molten aluminum [ 107 ]. When studying the metal of the transition layer of welded joints from dissimilar alloys, the EBSD and XRD methods are used to reveal the phase composition and high-speed video recording of laser welding of dissimilar metals [ 108 ].…”

“…This allows obtaining the mechanical properties of the joint at the level of 173 MPa and the elongation of 4.5%. Gao M. et al in [ 105 ] continue similar studies of the authors of [ 33 ] on Al/Fe also aimed at studying the offset of the laser beam on aluminum (∆D), the effect of the oscillation frequency on the interface formation (Al 5 Fe 2 ), hydrodynamic processes in the molten pool, in particular on the uniform distribution of Fe melt by stirring effects on the molten pool.…”

Microstructure and mechanical properties of TiB2 reinforced Al2319 matrix composites produced using laser-arc hybrid additive manufacturing

“…During the laser-arc hybrid welding of Al/steel dissimilar joints, Meng suppressed the formation of intermetallic compounds by oscillating beam, and obtained a uniform single layer of Al5Fe2 at an optimized frequency of 150 Hz. The tensile and bending properties of the joint were increased by 65% and 96%, respectively [16]. It can be seen from the above research that oscillating laser-arc hybrid welding has a significant effect on improving weld formation, reducing porosity, refining microstructure, improving composition uniformity and mechanical properties.…”

Microstructural evaluation in dissimilar liquid phase bonding of cast Al–Si alloy and stainless steel using pure zinc filler metal

“…low toughness Al 5 Fe 2 ) at the joint interface are the critical metallurgical challenges during dissimilar joining of Al/steel. The presence of brittle intermetallic compounds at the joint interface coupled with the creation of thermal stress induced by a significant thermal expansion mismatch between Al and steels during joining leads to the high susceptibility of Al/steel dissimilar joint to cracking [1][2][3][4].…”

“…Solid-state welding processes such as friction stir welding are viable candidates for dissimilar welding of Al and steels [4][5][6][7]. In addition, some metallurgical joining processes, such as resistance spot welding [1,8,9], laser welding [2], arc welding [10], laser/arc hybrid [3], etc., enable Al/steel dissimilar joining via establishing a liquid/solid interface during joining. In these cases, the formation of intermetallic compound (IMC) due to solid steel-liquid Al reaction is the outstanding challenge to achieve a strong bond.…”