S355J0W钢对脱硫弧菌和铜绿假单胞菌腐蚀的抑制机制  

Corrosion Inhibition Mechanism of S355J0W Steel Against Desulfovibrio vulgaris and Pseudomonas aeruginosa

作　　者：卢士航 张雪[1] 窦雯雯 陈士强 刘光洲 LU Shihang;ZHANG Xue;DOU Wenwen;CHEN Shiqiang;LIU Guangzhou(Institute of Marine Science and Technology,Shandong University,Qingdao 266237,China)

机构地区：[1]山东大学海洋研究院,青岛266237

出　　处：《中国表面工程》2024年第2期41-57,共17页China Surface Engineering

基　　金：国家自然科学基金(U2106206,42006042,42276212,42176043)。

摘　　要：微生物腐蚀(MIC)严重威胁着海洋工程设施的可靠性和安全性,制约着海洋经济的发展。钢中添加合金元素是进行海洋MIC防护的重要策略之一。采用表面分析、失重和电化学测试等方法,以EH36钢为对照,探究由多合金元素组成的S355J0W钢对典型海洋腐蚀性微生物(脱硫弧菌和铜绿假单胞菌)腐蚀的抑制机制。结果表明,S355J0W钢具有更优的耐MIC性能。在含脱硫弧菌的厌氧培养基和含铜绿假单胞菌的有氧培养基中,S355J0W钢的MIC速率均明显低于EH36钢。在脱硫弧菌培养基中,S355J0W钢的失重和最大点蚀深度是EH36钢的56%、70%。在铜绿假单胞菌培养基中,S355J0W钢的失重和最大点蚀深度是EH36钢的54%、47%。相较于EH36钢,S355J0W钢含有Cr、Ni、Nb元素和更多的Cu元素。一方面,S355J0W钢中的合金元素使其表面的产物膜更具有保护性(更高的膜电阻值);另一方面,合金元素导致S355J0W钢表面固着的脱硫弧菌和铜绿假单胞菌数量仅是EH36钢的22%、24%。更少的固着细菌数量直接导致更低的胞外电子传递速率,从而降低S355J0W钢的MIC速率。添加耐蚀和抑菌合金元素能够显著提高材料的耐MIC性能,研究结果为海洋MIC机理的探究提供了理论依据,为海洋结构钢MIC防护方法的设计与开发提供了新见解。Marine environments are extremely harsh and corrosive.Marine corrosion is mostly associated with the metabolic activity of microorganisms.Microbiologically influenced corrosion(MIC)seriously threatens the reliability and safety of marine engineering facilities and restricts the development of the marine economy.Many methods have been applied to prevent MIC in steels,such as coatings,biocides,cathodic protection,and MIC-resistant alloy steels.The development of MIC-resistant alloy steels by adding alloying elements is an important strategy for marine MIC prevention.Exploring MIC mechanisms can provide a theoretical basis for MIC prevention.Therefore,the inhibition mechanism of S355J0W steel,composed of multiple alloying elements(Cr,Ni,Nb,and Cu),on the MIC caused by typical marine corrosive microorganisms(Desulfovibrio vulgaris and Pseudomonas aeruginosa)is investigated using surface analysis,weight loss,and electrochemical tests,with EH36 steel as a control.The results show that D.vulgaris and P.aeruginosa can acquire electrons from the Fe(0)surface and promote steel corrosion through the biocatalytic reduction of sulfate and nitrate reactions by transferring the electrons harvested from steel to intracellular,respectively.Notably,in both the anaerobic medium containing D.vulgaris and the aerobic medium containing P.aeruginosa,S355J0W steel had a much lower MIC rate than EH36 steel.In the D.vulgaris medium,the weight loss and maximum pitting depth of S355J0W steel were 2.9 mg·cm−2 and 50.4μm,respectively,whereas these values for EH36 steel were 5.2 mg·cm−2 and 71.5μm,respectively:the weight loss and maximum pitting depth of S355J0W steel were 56%and 70%of those of EH36 steel,respectively.Meanwhile,in the enriched seawater with P.aeruginosa,the weight loss and maximum pitting depth of S355J0W steel were 2.5 mg·cm−2 and 26.3μm,respectively,and those of EH36 steel were 4.6 mg·cm−2 and 56.2μm,respectively:the weight loss and maximum pitting depth of S355J0W steel were 54%and 47%of those of EH36 steel,

关 键 词：合金元素 微生物腐蚀(MIC) 脱硫弧菌 铜绿假单胞菌 胞外电子传递(EET) 

分 类 号：TG171[金属学及工艺—金属表面处理]