Influence of welding parameters on distribution of wire feeding elements in CO₂ laser GMA hybrid welding

Abstract

The effect of welding parameters on the distribution of wire feeding elements has been investigated during CO 2 laser and pulsed gas metal arc hybrid welding process. The molten metal flow on the pool surface and inside of the samples was observed by a high speed video camera and an in situ X-ray transmission imaging system respectively. The results indicate that the fluid flow towards the inside of keyhole, namely inward flow, improves the homogeneity of weld metal. The distribution of alloying elements is more homogeneous in leading laser compared with leading arc, since both of the drag force of the plasma jet and momentum of droplet promote the inward flow in leading laser. Almost homogeneous distribution of alloying elements can be attained if the oxygen content in the shielding gas is more than 2%, since the Marangoni flow direction changes from outward to inward with increasing the oxygen content.

Hybrid welding with fiber laser and CO2 gas shielded arc

“…Fellmann and Kujanpää (2006) denoted that high quality joints might be produced in hybrid CO 2 laser-GMA welding of carbon steel with various compositions of the shielding gas and the best results were obtained by the addition of 2-5% CO 2 gas to helium-argon mixture. Moreover, a positive influence of oxygen addition to the shielding gas on the chemical homogeneity of the fusion zone was noted by Zhao, et al (2009). Almost homogenous distribution of alloying elements could be obtained when the oxygen content in the shielding gas was higher than 2%.…”

Mechanical properties and microstructures of hybrid laser MIG welded dissimilar Mg–Al–Zn alloys

“…Experimental research shows that it has taken a big progress in welding of aluminium alloys and steels. [14][15][16][17] Therefore, it has the potential to join magnesium alloys well.…”

Improvement of Filler Wire Dilution Using External Oscillating Magnetic Field at Full Penetration Hybrid Laser-Arc Welding of Thick Materials

“…In [16], it was found that a trailing gas m torch configuration helped in the mixing of the melt in the welding of 10 mm thick plates. T e approach was demonstrated in [17]. Moreover, a shielding gas containing more than 2% O2 homogeneous distribution of alloying elements in [17].…”

“…T e approach was demonstrated in [17]. Moreover, a shielding gas containing more than 2% O2 homogeneous distribution of alloying elements in [17]. One of the main reasons for uitable distribution is caused by the Marangoni effect, which mainly influences the flow behav the surfaces.…”