Fig. 1. LPBF process of W-Ti. (a) SEM image of W-Ti powder; (b) back-scaterred electron (BSE) image of powder morphology; (c) LPBF printing process; (d) LPBF-printed W-Ti alloy samples at different scan strategies

Fig. 2. Schematic diagrams of different scan strategies in LPBF experiment

Fig. 3. Surface morphologies of LPBF-printed W-Ti samples using different scan strategies. (a)(d) Island scan strategy; (b)(e) zigzag scan strategy; (c)(f) remelting scan strategy

Fig. 4. Densification behavior of LPBF-printed W-Ti samples using different scan strategies. (a) Island scan strategy; (b) zigzag scan strategy; (c) remelting scan strategy; (d) relative density comparison

Fig. 5. Microstructure analysis of LPBF-printed W-Ti. (a) Binary alloy phase diagram of W-Ti alloy; (b) typical XRD patterns of LPBF-printed W-Ti samples at different scan strategies; (c) SEM image of W-Ti samples printed at island scan strategy; (d) EDS analysis result of W-Ti samples printed at island scan strategy

Fig. 6. Residual stress measurement of LPBF-printed W-Ti samples. (a) Theoretical distribution of residual stress along building direction; (b) schematic of cos α method for residual stress test; (c) two-dimensional and three-dimensional Debye rings of LPBF-printed sample using island scan strategy; (d) two-dimensional and three-dimensional Debye rings of LPBF-printed sample using remelting scan strategy

Fig. 7.

Surface residual stress distribution of LPBF-printed samples along x and y directions. (a) (b) Island sacn strategy; (c) (d) remelting scan strategy

Fig. 8. Nano-indentation results of LPBF-printed W-Ti samples under different laser scan strategies. (a) Force-displacement curves; (b) elastic modulus and nanohardness

Fig. 9. Compression performance of LPBF-printed W-Ti samples under different laser scan strategies. (a) Stress-strain curves; (b) ultimate compressive strength (σ_bc) and fracture strain at break (δ)

Fig. 10. Fracture morphologies of LPBF-printed W-Ti samples at different scan strategies. (a) Island scan strategy; (b) zigzag scan strategy; (c) remelting scan strategy