Titanium alloys, usually known as non-corrodible material, are susceptible to microbiologically influenced corrosion (MIC) in marine environment. While titanium-zirconium (TiZr) alloys have been extensively studied in medical applications, the influence of microorganisms, especially marine microorganisms, on their corrosion behavior has not been explored. In this work, a TiZrCu alloy with a combination of excellent mechanical, anti-corrosion, and antibacterial properties was developed by optimizing the Cu content and grain refinement. Its MIC and antibacterial mechanisms against Pseudomonas aeruginosa, a representative marine microorganism, were systematically investigated. 5.5 wt% was determined as the optimal copper content. The fine-grained Ti-15Zr-5.5Cu (TZC-5.5FG) alloy maintained high MIC resistance, exhibiting a corrosion current of 5.7 ± 0.1 nA/cm² and an antibacterial rate of 91.8 % against P. aeruginosa. The mechanism of improved corrosion resistance was attributed to the denser passive film with high TiO₂ content and the lower surface potential difference ΔE. The release of Cu²⁺ ions, ΔE, and the generation of ROS are three major factors that contribute to the antibacterial performance of TiZrCu alloys. Compared to other available marine metals, TZC-5.5FG alloy exhibited superior comprehensive performance, including excellent mechanical properties and anti-MIC capacity, which make it a promising material for load-bearing applications in marine environment.

中文翻译：

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一种专为海洋环境量身定制的新型细晶粒 TiZrCu 合金，具有高抗微生物腐蚀性


钛合金，通常被称为不可腐蚀的材料，在海洋环境中容易受到微生物影响的腐蚀 （MIC）。虽然钛锆 （TiZr） 合金在医疗应用中已得到广泛研究，但微生物（尤其是海洋微生物）对其腐蚀行为的影响尚未得到探索。在本工作中，通过优化 Cu 含量和晶粒细化，开发了一种兼具优异机械、防腐蚀和抗菌性能的 TiZrCu 合金。系统研究了其 MIC 和对代表性海洋微生物铜绿假单胞菌的抗菌机制。5.5 wt% 被确定为最佳铜含量。细晶粒 Ti-15Zr-5.5Cu （TZC-5.5FG） 合金保持了较高的耐 MIC 性能，腐蚀电流为 5.7 ± 0.1 nA/cm²，对铜绿假单胞菌的抗菌率为 91.8 %。耐腐蚀性提高的机理归因于更致密的钝化膜、高 TiO₂ 含量和较低的表面电位差 ΔE。Cu²⁺ 离子的释放、Δ E 和 ROS 的产生是影响 TiZrCu 合金抗菌性能的三个主要因素。与其他可用的海洋金属相比，TZC-5.5FG 合金表现出卓越的综合性能，包括优异的机械性能和抗 MIC 能力，这使其成为海洋环境中承重应用的有前途的材料。