Fig. 1. Microstructures of base metals and pure niobium. (a) Ti6Al4V; (b) Inconel 718; (c) pure niobium

Fig. 2. Welding diagram

Fig. 3. Schematic of tensile samples

Fig. 4. Macroscopic cross-section morphology of joint welded at different heat input. (a) 48 J/mm; (b) 40 J/mm; (c) 34 J/mm

Fig. 5. Microstructures and EDS analysis of melting zone in joint welded at different heat input. (a) 40 J/mm; (b) 34 J/mm; (c) EDS analysis of each point in microstructure images

Fig. 6. Ti-Nb binary phase diagram

Fig. 7. Interface microstructure of Nb/Inconel 718 interface and chemical composition of each point.(a) Microstructure; (b) chemical composition

Fig. 8. Ni-Nb binary phase diagram

Fig. 9. XRD result of welded joint

Fig. 10. Schematic laser-induced eutectic reaction brazing

Fig. 11. Morphology of Nb/Inconel 718 interface formed at different heat input. (a) 40 J/mm; (b) 34 J/mm

Fig. 12. Microhardness distribution on cross-section of joint welded at different heat input. (a) 40 J/mm; (b) 34 J/mm

Fig. 13. Microhardness profiles at the Nb/Inconel 718 interface formed at different heat input. (a) 40 J/mm; (b) 34J /mm

Fig. 14. Tensile curves of Ti6Al4V/Nb/Inconel 718 dissimilar joints

Fig. 15. Tensile fracture morphology of joint welded at different heat input. (a) 40 J/mm; (b) 34 J/mm