Enhanced mechanical properties and formability of 316L stainless steel materials 3D-printed using selective laser melting

This study is conducted to develop an innovative and attractive selective laser melting (SLM) method to produce 316L stainless steel materials with excellent mechanical performance and complex part shape. In this work, the subregional manufacturing strategy, which separates the special parts from the components using an optimized process, was proposed. The results showed that produced 316L materials exhibited superior strength of~755 MPa and good ductility. In the as-built parts, austenite with preferred orientation of the (220) plane, δ-ferrite, and a small amount of CrO phases were present. In addition, the crystal size was fine, which contributed to the enhancement of the parts' mechanical properties. The structural anisotropy mechanism of the materials was also investigated for a group of half-sized samples with variable inclination directions. This technique was used to fabricate a set of impellers with helical bevels and high-precision planetary gears, demonstrating its strong potential for use in practical applications.