Fig. 1. Size of tensile sample

Fig. 2. Size of fatigue sample

Fig. 3. Weld macro-morphology. (a) Weld front and back of laser-MAG hybrid welding; (b) weld front and back of pulsed laser-MAG hybrid welding

Fig. 4. Morphology of cross section of welded joints. (a) Laser-MAG hybrid welding; (b) pulsed laser-MAG hybrid welding

Fig. 5. Regionalism partition of welded joint

Fig. 6. Microstructures of laser-MAG hybrid welded joints in different regions. (a) Upper of weld zone; (b) under of weld zone; (c) CGHAZ; (d) FGHAZ; (e) NFTZ

Fig. 7. Microstructures of pulsed laser-MAG hybrid welded joints. (a) Upper of weld zone; (b) under of weld zone; (c) CGHAZ; (d) FGHAZ; (e) NFTZ

Fig. 8. Hardness distributions of welded joints. (a) Hardness measurement paths; (b) hardness distribution along L1; (c) hardness distribution along L2

Fig. 9. Tensile sample and fracture morphology. (a) Fracture position of tensile sample; (b) SEM image of tensile fracture

Fig. 10. Comparison of S-N curves of welded joints

Fig. 11. Fatigue fracture morphology of laser-MAG hybrid welded joints at a cyclic stress amplitude of 370 MPa. (a) Macro-fracture; (b) fatigue source region; (c) crack propagation region; (d) final fracture region

Fig. 12. Fatigue fracture morphology of pulsed laser-MAG hybrid welded joints at a cyclic stress amplitude of 370 MPa.(a) Macro-fracture; (b) fatigue source region; (c) crack propagation region; (d) final fracture region