Fig. 1. Four shapes of welding spot. (a) Ring-welding spot; (b) C-welding spot; (c) oval-welding spot; (d) S-welding spot

Fig. 2. Material properties of GH3230. (a) Thermophysical properties; (b) mechanical properties

Fig. 3. Surface and cross-section morphologies of laser welding spots. (a) Ring-welding spot; (b) oval-welding spot; (c) C-welding spot; (d) S-welding spot

Fig. 4. Effect of linear energy on weld width. (a) Top weld width; (b) back weld width

Fig. 5. Tensile direction of samples

Fig. 6. Tensile force comparison of different shapes of welding spots

Fig. 7. Total laser energy comparison of different shapes of welding spots

Fig. 8. Comparison of tensile force per unit length

Fig. 9. Tensile force curves of joint at different parameters

Fig. 10. Relationship between width of fusion surface and tensile force

Fig. 11. Fracture morphologies of tensile samples with four shapes of welding spots. (a) Macro-morphologies; (b) micro-morphologies

Fig. 12. Microstructures of four welding spots. (a) Weld zone; (b) heat affected zone