Fig. 1. Morphology and particle size distribution of Ni₅₀Ti₅₀ powder. (a) Powder morphology; (b) particle size distribution

Fig. 2. Bulk samples and dimension of tensile samples of NiTi alloy fabricated with selected laser melting (SLM)

Fig. 3. Micro appearances of NiTi single track samples fabricated with selected laser melting under different process parameters

Fig. 4. Width of NiTi single track samples fabricated with selected laser melting under different process parameters

Fig. 5. Surface appearances and three-dimensional contour maps of NiTi bulk samples fabricated with constant laser power (P=150 W) and scanning speed (v=1100 mm/s), but different hatch spacing values. (a) h=115 μm; (b) h=103 μm; (c) h=90 μm; (d) h=77 μm; (e) h=64 μm

Fig. 6. Relative density and cross-section images of NiTi bulk samples fabricated with selected laser melting under different hatch spacing values

Fig. 7. XRD spectra of Ni₅₀Ti₅₀ powder and NiTi bulk samples fabricated with selected laser melting under different hatch spacing values

Fig. 8. Phase transformation behavior of Ni₅₀Ti₅₀ powder and NiTi bulk samples fabricated with selected laser melting under different hatch spacing values. (a) DSC curves; (b) change trend of phase transition temperature with hatch spacing

Fig. 9. Mechanical properties of NiTi bulk samples fabricated with selected laser melting under different hatch spacing values. (a) Compressive stress-strain curves; (b) tensile stress-strain curves

Fig. 10. Superelasticity of NiTi bulk samples fabricated with selected laser melting under hatch spacing of 77 μm. (a) Cyclic compressive stress-strain curves; (b) effect of cycle numbers on recoverable strain and irrecoverable strain

Fig. 11. Comparison of mechanical properties between our work and reported NiTi in recent years. (a) Compression performance; (b) tensile properties