Additive manufacturing enables in-situ alloying of multi-component materials for the development of novel and high-performance materials. Here laser powder bed fusion (LPBF) of SiC-reinforced 316L stainless steels metallic matrix composites (MMCs) for improved strength and wear resistance were investigated. The densification behaviour, microstructural evolution, crystallographic orientation and properties of the LPBF-processed MMCs with different SiC contents were systematically investigated. The formation mechanisms of pores and cracks are discussed. Microstructural observations reveal that the microstructure changes from equiaxed to dendritic with increasing SiC are related to the different temperature gradient and solidification rates. The SiC addition affects crystallographic orientation and causes grain refinement to 316L. In addition, micron SiC particles are refined to nano-scale after laser processing, which induces massive dislocations in the 316L matrix. The strength and tribological properties of 316L are significantly improved by SiC addition, in which the 9 vol% SiC reinforced MMC reaches a high tensile strength of about 1.3 GPa, together with a low wear rate of 0.77 × 10⁻⁵ mm³/Nm. The achieved strength and wear resistance are at the highest level among literature, and the underlying strengthening mechanisms are elucidated.

增材制造可实现多组分材料的原位合金化，以开发新型高性能材料。本文研究了SiC增强316L不锈钢金属基复合材料（MMC）的激光粉末床熔合（LPBF），以提高强度和耐磨性。系统研究了SiC含量不同的LPBF处理的MMC的致密行为，微观结构演变，晶体学取向和性能。讨论了气孔和裂纹的形成机理。显微组织观察表明，随着SiC含量的增加，从等轴晶向枝晶的显微组织变化与不同的温度梯度和凝固速率有关。SiC的添加会影响晶体学取向，并使晶粒细化至316L。此外，激光加工后，微米级的SiC颗粒被细化至纳米级，这会在316L基体中引起大量的位错。加入SiC可以显着改善316L的强度和摩擦学性能，其中9％（体积）的SiC增强MMC达到约1.3 GPa的高拉伸强度，而磨损率仅为0.77×10^-5 mm ³ / Nm。达到的强度和耐磨性在文献中处于最高水平，并且阐明了潜在的增强机制。