Fig. 1. Microstructure of Ti6Al4V titanium alloy base metal

Fig. 2. Cross-sectional morphologies of welded joints and weld seam sizes under different diode laser powers. (a) 1.0 kW; (b) 1.5 kW; (c) 3.0 kW; (d) weld seam size

Fig. 3. Top and bottom microstructures of weld seams under different semiconductor laser powers. (a) 1.0 kW, top; (b) 1.5 kW, top; (c) 3.0 kW, top; (d) 1.0 kW, bottom; (e) 1.5 kW, bottom; (f) 3.0 kW, bottom

Fig. 4. Physical drawing of tensile samples and engineering stress-strain curves. (a) Physical drawing of tensile samples; (b) engineering stress-strain curves

Fig. 5. Fracture morphologies of tensile test samples. (a) 1.0 kW; (b) 1.5 kW; (c) 3.0 kW

Fig. 6. Cross-sectional morphologies of welded joints and weld seam sizes under different welding speeds. (a) 30 mm·s^-1; (b) 60 mm·s^-1; (c) 120 mm·s^-1; (d) weld seam size

Fig. 7. Inverse pole figures and grain boundary distribution maps of weld seams under different welding speeds. (a)(d) 30 mm·s^-1; (b)(e) 60 mm·s^-1; (c)(f) 120 mm·s^-1

Fig. 8. Statistical results of grain sizes of weld seams under different welding speeds. (a) 30 mm·s^-1; (b) 60 mm·s^-1; (c) 120 mm·s^-1

Fig. 9. Statistical results of grain boundaries of weld seams under different welding speeds. (a) 30 mm·s^-1; (b) 60 mm·s^-1; (c) 120 mm·s^-1

Fig. 10. Physical drawing of tensile samples and engineering stress-strain curves. (a) Physical drawing of tensile samples; (b) engineering stress-strain curves

Fig. 11. Fracture morphologies of tensile test samples. (a) 30 mm·s^-1; (b) 60 mm·s^-1; (c) 120 mm·s^-1