The influence of the arrangement for fiber laser and TIG on the hybrid welding process

In this paper, high power fiber laser and DC TIG welding machine were used to carry out hybrid welding experiments. The influence of heat source relative position on welding process was studied from the aspects of weld surface forming, porosity, weld depth/weld width and dynamic behavior of molten pool/keyhole. The results showed that compared with the laser-guided welding, the weld surface roughness and contour height were higher, the mass loss of plate was smaller during the arc-guided welding. Compared with the arc-guided welding, the greater weld depth and the smaller weld width can be achieved when laser-guided. The different heat source arrangement will significantly affect the laser absorption of the plate, the angle of the front keyhole wall and the state of the plasma, so as to affect the weld depth and weld width. The maximum difference of weld depth between different arrangements of heat sources was about 20%. Further analysis showed that molten pool bulge near the front and back of the keyhole mouth were acted by the arc force along the welding direction, and the influence of this force on the liquid column was the main reason for the change of the weld surface shape in the hybrid welding with different guidance modes.