Seam gap bridging of laser based processes for the welding of aluminium sheets for industrial applications

Abstract

Laser welding has a large potential for the production of tailor welded blanks in the automotive industry, due to the low heat input and deep penetration. However, due to the small laser spot and melt pool, laser-based welding processes in general have a low tolerance for seam gaps. In this paper, five laserbased welding techniques are compared for their gap bridging capabilities: single-spot laser welding, twinspot laser welding, single-spot laser welding with cold wire feeding, twin-spot laser welding with cold wire feeding and laser/GMA hybrid welding. Welding experiments were performed on 1.1-and 2.1-mm-thick AA5182 aluminium sheets. The resulting welds were evaluated using visual inspection, cross sectional analysis with optical microscopy, tensile tests and Erichsen Cupping tests. The results show that the use of a filler wire is indispensable to increase the gap tolerance. A proper alignment of this wire with the laser spot(s) is crucial. With the single spot laser welding with cold wire feeding, a gap up to 0.6 mm could be bridged as opposed to a maximum allowable gap width of 0.2 mm for single-spot laser welding without filler wire. For 2.1-mm-thick sheets, the laser/GMA hybrid welding

Heat treatment of welded joints of steel 0.3С–1Cr–1Si produced by high-power fiber lasers

“…1, two electric ovens SNOL 7.2/1300 were used. The thermal processing was aimed at increase of plasticity [20], with maintaining high strength properties of the welded joint having a martensite structure [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] with hardness of 8500-9000 MPa. For studying the mechanical properties and microstructure, the samples were prepared from the welded blank No.1 (no heat treatment-NHT), No.…”

“…Laser welding is used for welding of austenitic steels of various classes [2,8], duplex [6,9], zinc-coated [10], microalloyed [30] steels, and a large number of works is devoted to hybrid welding with various technological methods for welding of thick stock materials [4,[8][9][10].…”

Study and Characterization of EN AW 6181/6082-T6 and EN AC 42100-T6 Aluminum Alloy Welding of Structural Applications: Metal Inert Gas (MIG), Cold Metal Transfer (CMT), and Fiber Laser-MIG Hybrid Comparison

“…This critical procedure can be solved by using the twin spot laser technique with filler wire or hybrid arc-laser welding, but will decrease the welding speed. One of the ways to solve this problem is the use of laser beam wobbling mode [11,12,[44][45][46][47][48][49][50].…”

The effect of laser beam wobbling mode in welding process for structural steels

“…In the last few years, lot of papers about laser welding with special technical applications, like hybrid laser arc welding [1][2][3][4][5][6], twin spot laser welding, laser welding with cold filler material [6], friction stir welding with laser tempering, hybrid welding with different combination arc leading, laser leading etc., were published. In addition, hybrid laser welding is used for dissimilar materials, like Fe-Al joint [7], bifocal laser beam welding "turbo-weld" for specimen with different thicknesses [8].…”

“…Original laser welding of thick and long plates requires final preparation, alignment, fixation, and welding process control. This problem can be solved using twin spot laser technique with filler wire or hybrid arc-laser welding [6][7][8][9][10][11][12][13][14], but it will decrease the welding speed. One of the ways to solve this problem is the use of a laser beam wobbling mode.…”