Selective laser melting (SLM) is an additive manufacturing (AM) technique designed to use a high energy density laser to fuse metallic powders for producing three-dimensional parts. So far, most studies of SLM have been focused on using virgin metal powders. There are few comprehensive studies on the microstructure and mechanical properties of SLM-produced parts using recycled powders, especially for maraging steels. In this study, we employ recycled steel powder (reused after 113 building cycles) in the SLM process to print multiple shaped components and systematically characterize the microstructure and mechanical properties (indentation, tensile, and Charpy testing). Our results show that maraging steel produced with recycled powder exhibit the nearly identical microstructure and mechanical properties (940 MPa yield strength, 1127 MPa ultimate tensile strength, 11 pct elongation, and 47.5 J room temperature impact fracture energy) to those produced using virgin powders. This study provides a useful generic guide towards using recycled metal powders in the SLM processing, promoting an economic solution to industrial productions.

选择性激光熔化（SLM）是一种增材制造（AM）技术，旨在使用高能量密度激光器融合金属粉末来生产三维零件。到目前为止，对SLM的大多数研究都集中在使用原始金属粉末上。很少有关于使用回收粉末的SLM生产零件的组织和力学性能的综合研究，特别是对于马氏体时效钢。在这项研究中，我们在SLM工艺中采用了回收的钢粉（在113个建造周期后重复使用），以印刷多个成形的部件，并系统地表征其微观结构和机械性能（压痕，拉伸和夏比测试）。我们的结果表明，采用再生粉末生产的马氏体时效钢具有几乎相同的组织和力学性能（屈服强度940 MPa，与使用原始粉末生产的产品相比，极限拉伸强度为1127 MPa，极限拉伸强度为11 pct，室温冲击断裂能为47.5J。这项研究为在SLM加工中使用再生金属粉末，促进工业生产的经济解决方案提供了有用的通用指南。