Fig. 1. Schematics of sample preparation. (a) Sampling location; (b) tensile sample size

Fig. 2. Schematics of repair path

Fig. 3. Morphologies and density values of restoration areas. (a) Morphology of 1400 W restoration area; (b) morphology of 1600 W restoration area; (c) morphology of 1800 W restoration area; (d) morphology of 2000 W restoration area; (e) density values under different powers

Fig. 4. XRD patterns of specimen repaired by laser cladding

Fig. 5. Positions and results of Mg solubility measurement under different laser powers. (a) Measurement position at 1400 W; (b) measurement position at 1600 W; (c) measurement position at 1800 W; (d) measurement position at 2000 W; (e) measurement results at different powers

Fig. 6. SEM and EDS images of microstructures. (a) SEM image of binding area between restoration zone and matrix; (b) EDS image of restoration zone; (c) SEM image of interlamellar columnar crystals in restoration zone; (d) SEM image of equiaxed crystals in central region of fuse

Fig. 7. SEM images of interlayer fusion line. (a) Remelting zone at 1400 W; (b) local amplification of Fig.7(a); (c) remelting zone at 2000 W; (d) local amplification of Fig.7(c)

Fig. 8. Pore characteristics and distribution map. (a) Process pores; (b) metallurgical pores; (c) oxide film pores; (d) shrinkage pores;

Fig. 9. Schematics of process hole formation. (a) Irregular cavity forms by eruption of low-melting elements during laser irradiation; (b) AlSi10Mg powder enters cavity with feeding powder gas; (c) cavity reaches bottom area of molten pool with Marangoni stream; (d) molten pool solidifies and irregular pores form in cavity

Fig. 10. Metallurgical hole formation diagrams. (a) Formation of tiny bubbles at bottom of molten pool; (b) movement of tiny bubbles with Marangoni stream; (c) bubbles merge and become larger during ascent; (d) molten pool solidifies and bubbles lead to formation of spherical pores

Fig. 11. Tensile curves and photos of tensile fracture specimens. (a) Tensile curves; (b) fracture positions of tensile specimens

Fig. 12. Density, tensile strength, and elongation under different laser powers

Fig. 13. Fracture morphologies of tensile parts. (a) Fracture morphology at 1400 W; (b) fracture morphology at 1600 W; (c) fracture morphology at 1800 W; (d) fracture morphology at 2000 W

Fig. 14. Hardness distribution curves under different powers