Analysis of Droplet Transfer and Porosity Characteristics in Laser-MAG Hybrid Welding of Edge Joint

In this paper, the morphological characteristics of arc plasma and droplet transfer during the alternating magnetic field-assisted narrow gap groove laser-MIG (metal inert gas) hybrid welding process were investigated. The characteristics of arc plasma and droplet transfer, electron temperature, and density were analyzed using a high-speed camera and spectrum diagnosis. Our results revealed that the arc maintained a relatively stable state and rotated at a high speed to enhance the arc stiffness, and further improved the stability of the arc under the alternating magnetic field. The optimum magnetic field parameters in this experiment were B = 16 mT and f = 20 Hz, the electron temperature was 9893.6 K and the electron density was 0.99 × 1017 cm−3 near the bottom of the groove, which improved the temperature distribution inside the narrow gap groove and eliminated the lack of sidewall fusion defect. Compared to those without a magnetic field, the magnetic field could promote droplet transfer, the droplet diameter decreased by 17.6%, and the transition frequency increased by 23.5% (owing to the centrifugal force during droplet spinning and electromagnetic contraction force). The width of the weld bead was increased by 12.4% and the pores were also significantly reduced due to the stirring of the magnetic field on the molten pool.

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Effects of Shielding Gas Parameters on Droplet Transfer and Bead Profile Prepared by CO2LaserMAG Hybrid Welding

Applied laser ◽

10.3788/al20103006.0503 ◽

2010 ◽

Vol 30 (6) ◽

pp. 503-507

Author(s):

刘明辉 Liu Minghui ◽

张宏 Zhang Hong ◽

刘双宇 Liu Shuangyu ◽

石岩 Shi Yan

Keyword(s):

Hybrid Welding ◽

Shielding Gas ◽

Droplet Transfer ◽

Bead Profile

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A study of droplet transfer behavior in ultra-narrow gap laser arc hybrid welding

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-016-8699-9 ◽

2016 ◽

Vol 87 (9-12) ◽

pp. 2997-3008 ◽

Cited By ~ 10

Author(s):

Ruoyang Li ◽

Jun Yue ◽

Ran Sun ◽

Gaoyang Mi ◽

Chunming Wang ◽

...

Keyword(s):

Hybrid Welding ◽

Narrow Gap ◽

Droplet Transfer ◽

Transfer Behavior

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Droplet transfer during conventional gas metal arc and plasma-gas metal arc hybrid welding with Al 5183 filler metal

Current Applied Physics ◽

10.1016/j.cap.2012.03.001 ◽

2012 ◽

Vol 12 ◽

pp. S178-S183 ◽

Cited By ~ 9

Author(s):

C.-H. Kim ◽

Y.-N. Ahn ◽

K.-B. Lee

Keyword(s):

Filler Metal ◽

Hybrid Welding ◽

Droplet Transfer

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Experimental investigation on arc characteristic and droplet transfer in CO2 laser–metal arc gas (MAG) hybrid welding

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2013.03.051 ◽

2013 ◽

Vol 62 ◽

pp. 604-611 ◽

Cited By ~ 31

Author(s):

Shuangyu Liu ◽

Fengde Liu ◽

Chunying Xu ◽

Hong Zhang

Keyword(s):

Experimental Investigation ◽

Co2 Laser ◽

Hybrid Welding ◽

Droplet Transfer

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The effect of shielding gas composition in CO2 laser—gas metal arc hybrid welding

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/09544054jem944 ◽

2008 ◽

Vol 222 (11) ◽

pp. 1315-1324 ◽

Cited By ~ 18

Author(s):

H-B Chae ◽

C-H Kim ◽

J-H Kim ◽

S Rhee

Keyword(s):

Molten Metal ◽

High Speed ◽

Dominant Role ◽

Ambient Air ◽

Metal Transfer ◽

Video Observation ◽

Hybrid Welding ◽

Shielding Gas ◽

Droplet Transfer ◽

Laser Induced Plasma

In carbon dioxide (CO2) laser—gas metal arc hybrid welding, a shielding gas is supplied to isolate the molten metal from the ambient air, suppress the laser-induced plasma, remove the plume out of the keyhole, and stabilize the metal transfer. In this study, a shielding gas consisting of helium, argon, and CO2 was used, and its effects on the composition of the welding phenomena, such as behaviours of laser-induced plasma generation, molten pool flow, and droplet transfer in gas metal arc welding, were investigated. High-speed video observation was used to investigate the welding phenomena inside the arc regime. Consequently, helium was found to have a dominant role in suppressing laser-induced plasma; minimum helium content at a laser power of 8 kW was suggested for laser autogenous and hybrid welding. Argon and CO2 govern the droplet transfer and arc stability. A 12 per cent addition of CO2 stabilizes the metal transfer and eliminates undercut caused by insufficient wetting of molten metal.

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