Exceptional strength and antibacterial durability in hierarchically structured Cu-bearing 316L stainless steel through additive manufacturing

作者：Chuanxi Ren, Tao Liang, Shan Jin, Zizheng Song, Xingdong Dan, Qi Liu, Yixuan Sun, Meng Wang, Yunbo Du, Chunjin Wang, Haobo Pan, Zibin Chen · 发表于：Journal of Materials Research and Technology · 年份：2025 · DOI：10.1016/j.jmrt.2025.04.220 · 被引用次数：13 · 研究领域：Additive Manufacturing Materials and Processes、Titanium Alloys Microstructure and Properties、Welding Techniques and Residual Stresses

As crucial materials within the biomedical domain, antibacterial stainless steels have garnered widespread utilization across various sectors. However, both the mechanical properties and antibacterial efficacy remain suboptimal in antibacterial stainless steels processed with traditional methods, including casting, forging, rolling, and multiple heat treatments. This inherent limitation significantly constrains the range of potential applications for these materials. Here, we report on a novel in-situ alloying strategy to fabricate hierarchically structured Cu-bearing 316L steels using additive manufacturing . Our approach results in an augmented yield strength exceeding 560 MPa, with the ultimate tensile strength near 600 MPa while preserving commendable ductility. Moreover, these high-strength Cu-bearing 316L stainless steels exhibit excellent antibacterial ability against both Escherichia coli and Staphylococcus aureus , with antibacterial rates reaching an impressive 100 %. The extraordinary strength enhancement in additively manufactured Cu-bearing 316L stainless steels originates from the synergistic interplay of multiple strengthening mechanisms due to hierarchical microstructure, including fine gains, cellular structure, deformed twins, stacking faults, and microbands . Simultaneously, the exceptional antibacterial ability could be traced to the heterogeneous distribution of Cu, printing defects and high-density grain boundaries in additively manufactured Cu-bearing 3...