Fig. 1. Schematics of welding. (a) Schematic of aluminum alloy/steel sample; (b) trajectory of laser beam

Fig. 2. Macroscopic morphology of welds obtained at typical welding parameters

Fig. 3. Cross-sectional morphology of welds obtained at typical welding parameters

Fig. 4. Interfacial structure of welded joint obtained with conventional laser welding. (a) In the bottom of interface; (b) in the aluminum alloy/steel interface

Fig. 5. Interfacial microstructures of welded joints obtained with laser wobble welding. (a)(b) Linear laser welding; (c)(d) circular laser welding

Fig. 6. Element distribution in welded joints. (a) Welded joint obtained with conventional laser welding(No.2);(b) welded joint obtained with linear laser welding (No.5); (c) welded joint obtained with circular laser welding (No.12)

Fig. 7. Tensile-shear strength of aluminum alloy/steel welded joints obtained at different welding processes

Fig. 8. Typical fracture positions of aluminum alloy/steel welded joints. (a) Fracture at aluminum alloy side; (b) fracture at the interface; (b) fracture at stainless steel side