Microstructural evolution, mechanical properties and tribological behavior of SiC reinforced 316L matrix composites fabricated by additive manufacturing

Selective laser melting (SLM) has been proved to be a promising additive manufacturing technique for production of high-performance metal matrix composites (MMCs) with unique microstructures. In this study, the SiC- reinforced 316L MMCs were prepared by SLM and the effects of SiC addition on the densification, microstructure evolution, mechanical properties and tribological behavior were systematically investigated. The SiC/316L MMCs fabricated by SLM were close to full density with high relative density over than 99.7%. The grains were significantly refined, and dislocation density was greatly enhanced with the addition of SiC particles. Tensile tests show that tensile strength of the specimens increased by 81.8% from 707 to 1285 MPa and yield strength increased by 72.7% from 543 to 938 MPa with the addition of SiC. In addition, the tribological behavior of MMCs with SiC addition are much superior to the pure 316L. The underlying strengthening mechanisms are discussed. The findings provide a new perspective on ceramic particles reinforced stainless steel MMCs with unique microstructure and excellence performance.