Study on characteristics of droplet transfer in low power pulsed laser-induced MAG hybrid welding with varied workpiece inclination angles.

• Low power pulsed laser-induced MAG hybrid welding can be applied to welding at a certain workpiece inclination angle, with excellent welding stability, proving its potential for application in all position welding. • The mechanism of D LA and workpiece inclination angle on droplet transfer in low power pulsed laser-induced MAG hybrid welding was revealed. • This work provides a theoretical basis for the popularization and application of laser-induced MAG all-position hybrid welding technology. In this work, the effects of workpiece inclination angles (θ), distance between laser spot and wire tip (D LA) on arc morphology, droplet transfer characteristics and stability were investigated by high-speed images (HSI), mathematical statistics and real-time electric signals. The coupling effect of heat source was evaluated by taking penetration as the main reference index. At the same time, the stability of the droplet transfer was evaluated based on the droplet transfer characteristics and the variation coefficient of current and voltage. The results showed that D LA had significant effect on droplet transfer in laser- induced MAG hybrid welding with varied workpiece angles. At D LA was 1 mm, the laser plasma compressed the arc, leading to the increase of the electromagnetic resistance of droplet transfer, which would prolong the formation and shedding time of droplet, making the droplet transfer mode change from "multi drop per pulse" to "one drop per pulse", and improving the stability of droplet transfer. The D LA affected the droplet transfer path and space instantaneous flight velocity. When D LA was −1 and 1 mm, the displacement of the droplet transfer reaches the minimum and maximum, respectively. When D LA was 1 mm, the droplet transfer was the most stable and maximum velocity could be obtained with varied workpiece inclination angles. This work provides a theoretical basis for the popularization and application of laser-induced MAG all-position hybrid welding technology. [ABSTRACT FROM AUTHOR]