Fig. 1. 316L stainless steel powders. (a) SEM image of the powders; (b) particle size distribution of the powders

Fig. 2. Additive/subtractive hybrid machine tool. (a) Main components; (b) appearance

Fig. 3. Laser scanning strategy

Fig. 4. Relative density of the SLM samples

Fig. 5. Sample structure defect. (a) Lack-of-fusion defects; (b) spherical pores; (c) cracks and lack-of-fusion defects

Fig. 6. Microhardness under different SLM parameters

Fig. 7. Sample indentation and microstructure. (a)(b) SLM sample indentation; (c)(d) microstructure of SLM sample; (e) microstructure of cast sample

Fig. 8. Initial surface before wear test. (a) SLM formed surface; (b) HASM surface; (c) milled surface of cast

Fig. 9. Coefficient of friction. (a) Polished surfaces under different energy densities; (b) different surfaces of SLM samples; (d) milled surfaces of cast 316L stainless steel

Fig. 10. Wear rates. (a) Wear rates under different energy densities; (b) wear rates corresponding to different initial surfaces

Fig. 11. Evolution of wear track morphology with time. (a)-(c) Surface processed by SLM; (d)-(f) HASM surface; (g)-(i) milled surface of cast 316L stainless steel

Fig. 12. Wear track morphology after sliding for 30 min. (a)-(f) SLM sample; (g)-(i) casting sample

Fig. 13. Influence of defects on coefficient of friction and wear rate. (a) Pore near asperity; (b) hard debris seized by pores; (c) pores got involved in friction; (d) hard debris stuffing in pores

Fig. 14. EDS analysis of element composition on worn surface. (a)-(c) SLM sample; (d)-(f) casting sample