Fig. 1. Welding experimental set-up and schematic of welding process. (a) Photo of welding experimental set-up; (b) underwater local dry device and schematic of welding process

Fig. 2. Schematic of sampling and sample dimension. (a) Schematic of sampling; (b) dimensions of metallographic and tensile samples

Fig. 3. Forming of 316L stainless steel laser weld surfaces under different parameters

Fig. 4. Cross-sectional morphologies of welds under different parameters

Fig. 5. Characters of weld cross-sectional morphology under different parameters

Fig. 6. Equilibrium phase diagram of weld and Schaeffler diagram. (a) Equilibrium phase diagram of weld; (b) Schaeffler diagram^[13]

Fig. 7. Microstructures of BM and weld under different parameters

Fig. 8. Welded joint samples after tensile fracture

Fig. 9. Tensile curves of welded joint samples. (a) Joint samples welded at different drainage air pressures; (b) joint samples welded at different water depths

Fig. 10. Macro-fracture surfaces of tensile samples

Fig. 11. Micro-morphologies of tensile fracture surfaces

Fig. 12. Tensile fracture path of welded joints