Fig. 1. Area to be repaired

Fig. 2. Morphologies of TC4 powder. (a) Microscopic morphology of powder; (b) surface morphology of powder

Fig. 3. Diagram of repair progress

Fig. 4. Path planning diagrams. (a) Front view; (b) top view

Fig. 5. Macroscopic morphology of the sample after repair

Fig. 6. Microstructure of α+β in base metal. (a) Metallographic image, ×300; (b) metallographic image, ×1000

Fig. 7. Basketweave structure in HAZ

Fig. 8. Colonies structure in HAZ

Fig. 9. Martensite with α phase in HAZ

Fig. 10. β columnar crystal in AM

Fig. 11. Widmanstatten structure in AM

Fig. 12. Widmanstatten structures at different positions in AM. (a) Bottom; (b) middle; (c) top

Fig. 13. Distribution diagrams after multiple repairs. (a) First repair; (b) second repair; (c) third repair

Fig. 14. Hardness distributions after multiple repairs. (a) First repair; (b) second repair; (c) third repair