Fig. 1. Schematics of longitudinal magnetic field-assisted narrow gap laser-MIG multi-layer welding process. (a) Welding process; (b) groove size of stainless steel plate; (c) spatial position of laser and wire

Fig. 2. Size of notched fatigue specimen

Fig. 3. Surficial morphology of welded joints prepared at different magnetic induction intensities

Fig. 4. Cross-sectional morphology of welds prepared at different magnetic induction intensities. (a) 0 mT; (b) 6 mT; (c) 12 mT; (d) 18 mT; (e) 24 mT

Fig. 5. Typical formation parameters characterizing cross-section of weld

Fig. 6. Effects of magnetic induction intensity on cross-sectional formation parameters of weld. (a) Formation parameters for upper hybrid welds; (b) area parameters for upper and lower hybrid welds

Fig. 7. Phase transformation diagram of 316L stainless steel

Fig. 8. XRD results of welded joints prepared at magnetic induction intensities of 0 mT and 18 mT. (a) Statistical graph; (b) curve graph

Fig. 9. Influences of magnetic induction intensity on ferrite in upper interlayer (between upper hybrid layer and lower hybrid layer) and lower interlayer (between lower hybrid layer and laser layer)

Fig. 10. Microstructures in HAZ of upper and lower hybrid layers

Fig. 11. Morphology of γ grains in central area of upper welds and interlayers

Fig. 12. Relationship of elongated distance versus cycle time for samples prepared at magnetic induction intensities of 0 mT and 18 mT

Fig. 13. Propagation direction and width of crack in weld