Purpose

Low-alloy structural steels (LASS) face severe microbiologically influenced corrosion (MIC) in their service environments. To mitigate this issue, Cu is often used as an alloying element owing to its intrinsic antimicrobial activity. However, the antibacterial performance and biofilm resistance of Cu-containing LASS (Cu-LASS) are still unclear. This study aims to analyze the effect of Cu addition to 420 MP LASS on its MIC by the Pseudomonas aeruginosa biofilm.

Design/methodology/approach

Scanning electron microscope, confocal laser scanning microscope and X-ray photoelectron spectroscopy were used to analyze the surface morphology and composition of corrosion products. The antibacterial activities of Cu-LASS were analyzed by the spread-plate method. In addition, electrochemical analysis was conducted to characterize the corrosion behavior of the produced alloy.

Findings

Bacterial analysis and morphological observation confirmed a reduced sessile cell count and inactivation of the P. aeruginosa biofilm on the surface of Cu-LASS coupons. Electrochemical measurements showed that Cu-LASS exhibited large polarization and charge-transfer resistances, which indicated excellent MIC resistance. This significantly enhanced resistance to MIC could be explained by the synergistic effect of released Cu²⁺ from the Cu-LASS surface and immediate contact to Cu-rich phase in the surface and the release of Cu²⁺ ions from the Cu-LASS surface.

Originality/value

The effect of Cu addition on the MIC resistance and antibacterial performance of LASS is seldom reported. It is necessary to investigate the corrosion resistance of Cu-LASS and clarify its antibacterial mechanism. This paper fulfills this need.

中文翻译：

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低合金结构钢中添加铜对铜绿假单胞菌生物膜抗腐蚀性能的影响

目的

低合金结构钢 (LASS) 在其使用环境中面临严重的微生物腐蚀 (MIC)。为了缓解这个问题，由于其固有的抗菌活性，Cu 通常被用作合金元素。然而，含铜LASS（Cu-LASS）的抗菌性能和生物膜耐受性尚不清楚。本研究旨在分析铜在 420 MP LASS 中添加对铜绿假单胞菌生物膜MIC 的影响。

设计/方法/方法

采用扫描电子显微镜、激光共聚焦扫描显微镜和X射线光电子能谱分析腐蚀产物的表面形貌和成分。Cu-LASS的抑菌活性采用平板法分析。此外，还进行了电化学分析以表征所生产合金的腐蚀行为。

发现

细菌分析和形态学观察证实，Cu-LASS 试样表面上的无柄细胞计数和铜绿假单胞菌生物膜的灭活。电化学测量表明，Cu-LASS 表现出大的极化和电荷转移电阻，这表明具有优异的 MIC 电阻。这种显着增强的 MIC 抗性可以通过从 Cu-LASS 表面释放的 Cu ²⁺和与表面中富铜相的直接接触以及从 Cu-LASS 表面释放 Cu ^{2+ 离子}的协同效应来解释。

原创性/价值

Cu添加对LASS的MIC抗性和抗菌性能的影响鲜有报道。有必要研究Cu-LASS的耐腐蚀性并阐明其抗菌机制。本文满足了这一需求。