Fig. 1. Schematic of A356/6082 laser overlap welding

Fig. 2. Schematic of tensile shear experiment

Fig. 3. Weld morphologies under different overlapping forms. (a) 6082/A356; (b) A356/6082

Fig. 4. Pore statistical results under different overlapping forms. (a)(b) Laser power of 4.2 kW; (c)(d) laser power of 4.8 kW; (e)(f) laser power of 5.4 kW

Fig. 5. Statistical results of pores in welded joints under different overlapping forms and laser powers. (a)(b) Number of pores; (c) pore diameter; (d) porosity

Fig. 6. Thermophysical properties of 6082 and A356 aluminum alloys. (a)(b) 6082; (c)(d) A356

Fig. 7. Molten pool photos by high speed camera under different overlapping forms. (a)‒(d) 6082/A356; (e)‒(h) A356/6082

Fig. 8. Distributions of pores in longitudinal section of 6082/A356 overlapped joint. (a) Overall distribution; (b) pore annexation;

Fig. 9. Distributions of pores in 6082/A356 overlapped joint. (a)(b) Longitudinal section at center of entire weld; (c)(d) longitudinal section of fusion line on both sides of weld; (e) cross section of weld

Fig. 10. Crack distributions of 6082/A356 overlapped joint. (a)(b) Longitudinal section of weld; (c) cross section of weld

Fig. 11. Cracks of 6082/A356 overlapped joints. (a) Left side of transition position; (b) right side of transition position; (c) crystallization crack

Fig. 12. Element distributions of 6082/A356 overlapped joint. (a) Scan position; (b) Al; (c) Si; (d) Mg

Fig. 13. Tensile and shear tests of different overlapped joints. (a) Tensile shear curves; (b) schematic of fracture location

Fig. 14. Fracture morphologies of A356/6082 overlapped joint. (a) Macroscopic morphology; (b) crack source; (c) cleavage plane;