Fig. 1. 316L stainless steel powder. (a) Morphology; (b) particle size distribution

Fig. 2. Formation process of SLM block

Fig. 3. Tensile specimen. (a) Geometric size; (b) finished product

Fig. 4. Surface morphologies of samples under different scanning speeds and hatch spaces. (a) 500 mm·s-1; (b) 750 mm·s-1; (c) 1000 mm·s-1; (d) 1250 mm·s-1

Fig. 5. Densities of samples under different scanning speeds. (a) 500 mm·s-1; (b) 750 mm·s-1; (c) 1000 mm·s-1; (d) 1250 mm·s-1

Fig. 6. Cross-sectional morphologies of samples under different scanning speeds when hatch space is 110 μm. (a) 500 mm·s-1; (b) 750 mm·s-1 ; (c) 1000 mm·s-1 ; (d) 1250 mm·s-1

Fig. 7. Sample forming defects. (a) Spatter phenomenon; (b) spatter defect; (c) big blow hole; (d) unmelted defect; (e) balling phenomenon; (f) balling defect; (g) small blow hole; (h) crack

Fig. 8. Formation process of spatter and pore

Fig. 9. Formation process of balling and pore

Fig. 10. Formation process of blow hole. (a) Low speed big blow hole; (b) high speed small blow hole

Fig. 11. Microstructures of samples under different scanning speeds. (a) 750 mm·s-1; (b) 500 mm·s-1; (c) 750 mm·s-1

Fig. 12. Tensile properties of samples under different hatch spaces when scanning speed is 750 mm·s-1