Fig. 1. Schematic of laser-MIG hybrid welding process

Fig. 2. Schematic of droplet transfer

Fig. 3. Geometry of calculation domain

Fig. 4. Distributions of temperature (left) and flow field (right) on longitudinal cross section of weld pool at different time (Test 1, white line in right picture is steamline). (a) t=1.007 s; (b) t=1.146 s; (c) t=1.248 s; (d) t=1.317 s; (e) t=1.429 s

Fig. 5. Positions of selected transverse cross section

Fig. 6. Distributions of temperature on transverse cross section of weld pool at different positions (Test 1). (a) x=24 mm; (b) x=22 mm; (c) x=20 mm; (d) x=16 mm; (e) x=12 mm; (f) x=10 mm

Fig. 7. Distributions of temperature (left) and flow field (right) on horizontal cross section of weld pool at different time(Test 1, z=0.3 mm). (a) t=1.0367 s; (b) t=1.1468 s; (c) t=1.2407 s; (d) t=1.3175 s; (e) t=1.4299 s; (f) t=1.6471 s

Fig. 8. Keyhole depth versus time (Test 1)

Fig. 9. Simulated (left) and experimental (right) results of transverse cross section of weld

Fig. 10. Effect of laser-arc tandem position on temperature and flow field on longitudinal cross section of weld pool (left is laser leading, Test 2; right is arc leading, Test 1; white line in flow field picture is streamline). (a) t=1.2495 s; (b) t=1.3658 s

Fig. 11. Effect of laser-arc tandem position on temperature of horizontal cross section of weld pool (left is laser leading, Test 2; right is arc leading, Test 1; white line in flow field picture is streamline). (a) t=1.0990 s; (b) t=1.1521 s