Fig. 1. Schematic of SLM forming. (a) Schematic of SLM working area; (b) schematic of forming bin sintering

Fig. 2. Powder morphology and particle size distribution. (a) Powder morphology; (b) particle size distribution

Fig. 3. Relative density versus energy density

Fig. 4. Defect and mechanism of defect generation. (a) Model of generation of pore caused by insufficient energy density; (b) model of generation of pore caused by blowing protective gas; (c) pores and cracks in formed sample; (d) micropores and large pores in formed sample

Fig. 5. XRD analysis results of powder and formed sample

Fig. 6. OM and SEM images of IN625. (a) Laser scan path on X-Y plane of OM; (b) columnar grain on X-Y plane of OM;(c) SEM image on X-Y plane; (d) OM morphology of molten pool; (e) OM morphology on X-Z plane; (f) SEM image on X-Z plane

Fig. 7. Microstructure of sample fabricated by SLM. (a) Surface carbide composition; (b) cellular and columnar grains; (c) bright white and dark areas of columnar grain; (d) bright white and dark areas of cellular grain

Fig. 8. Stain-stress curve of IN625

Fig. 9. Fracture morphology of IN625 sample. (a) Macro fracture; (b) dimples