Fig. 1. Experimental device diagrams. (a) Observation of spatters and molten pool; (b) spatter collection device

Fig. 2. Formation process of spatter particles

Fig. 3. Probability distribution of spatter particle size

Fig. 4. Variations of plume and spatters characteristics with defocus

Fig. 5. Relationship between molten pool and defocus

Fig. 6. Variations of plate mass loss and number of spatters with defocus

Fig. 7. Variations of penetration, weld width, and keyhole diameter with defocus

Fig. 8. Schematic of calculating the inclination angle of the front keyhole wall

Fig. 9. Variation of tilt angle of the front keyhole wall with the defocus

Fig. 10. Relationship between metal vapor and spatter