PAW−MIG wire oscillating hybrid welding technology

In order to solve the problem of double arc repulsion in the existing PAW−MIG hybrid welding process, a new welding process based on the regular change of MIG wire displacement was proposed, which combined MIG wire oscillation with plasma arc in common weld pool. The welding process test was carried out by adjusting the rotation (oscillation frequency) and amplitude of MIG welding wire motor. The results show that with the increase of rotational speed (oscillation frequency), the repulsion between plasma arc and MIG arc decreases and the coupling trend increases. Especially when the rotational speed is 2000 r/min(oscillation frequency 33 Hz), the common weld pool effect is obvious. When the amplitude of MIG torch is 1 mm, the arc shape is the most stable. When the oscillation frequency and amplitude are too large, it is not conducive to the stability of welding process. The oscillation speeds up the droplet transition frequency so that the tip of the welding wire presents a small droplet transition and reduces the welding splash. The mechanical properties of the butt test show that the tensile strength and bending strength increase first and then decrease with the increase of the oscillation frequency. The oscillation enhances the stirring ability of the molten pool metal and effectively improves the mechanical properties of the welded joint.