Cu含量对管线钢耐微生物腐蚀性能的影响  

Effect of Copper Content on the MIC Resistance in Pipeline Steel

作　　者：曾云鹏 严伟[2,3] 史显波[2,3] 闫茂成[2] 单以银[2,3] 杨柯[2] ZENG Yunpeng;YAN Wei;SHI Xianbo;YAN Maocheng;SHAN Yiyin;YANG Ke(School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China;Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;CAS Key Laboratory of Nuclear Materials and Safety Assessment,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China)

机构地区：[1]中国科学技术大学材料科学与工程学院,沈阳110016 [2]中国科学院金属研究所师昌绪先进材料创新中心,沈阳110016 [3]中国科学院金属研究所中国科学院核用材料与安全评价重点实验室,沈阳110016

出　　处：《金属学报》2024年第1期43-56,共14页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目No.U1906226。

摘　　要：含Cu耐微生物腐蚀管线钢的开发和应用是解决管道微生物腐蚀难题的有效措施。本工作利用电化学测试及SEM、激光共聚焦显微镜(CLSM)等分析技术,研究了不同Cu含量(0、0.7%、1.34%,质量分数)的X65级管线钢在无菌和接种硫酸盐还原菌(SRB)的近中性模拟土壤浸出液(NS4)中的腐蚀行为,为耐微生物腐蚀管线钢的优化设计提供依据。结果表明,随着Cu含量的升高,含Cu管线钢的抗菌性能和耐蚀性能均有所提高;当Cu含量从0增加到0.70%时,试样表面的点蚀坑密度从714 cm^(-2)下降到244 cm^(-2);当Cu含量达到1.34%时,点蚀坑密度进一步下降到67 cm^(-2);含Cu钢在腐蚀过程中持续释放的铜离子在接菌环境中的杀菌作用和其对腐蚀产物层的改善作用,以及其在无菌环境中所形成的Cu2O等保护性腐蚀产物是含Cu管线钢具有优异耐蚀性能的关键原因。Microbiologically induced corrosion(MIC),particularly those caused by sulfate-reducing bacteria(SRB),is considered as a destructive mechanism in buried pipeline steels,which has received considerable attention since its discovery a century ago.Research has shown that sessile cells that are attached to a metal surface embedded in biofilms with extracellular polymeric substances(EPS)are responsible for the occurrence of MIC.However,the commonly used MIC control strategy,i.e.,biocides,cannot perform sterilization of sessile cells because of the protection of the biofilm.Cu-bearing pipeline steel is a newly developed steel that can be used for MIC control in buried pipes.The continuous release of cytotoxic Cu ions from the steel matrix leads to MIC resistance.However,the influence of Cu content on MIC resistance remains unclear.A lower Cu content in steel is not beneficial to its MIC resistance,whereas a higher Cu content can increase the cost and may cause“hot shortness”during thermal processing.Therefore,clarifying the influence of Cu content on the properties of Cu-bearing pipeline steel is important for the practical application of the steel.In the present study,the influence of Cu content(0,0.7%,and 1.34%;mass fraction)on the corrosion behavior of X65 grade Cu-bearing pipeline steel was investigated through electrochemical measurements and surface analysis during 14 d immersion in sterile and SRB-inoculated NS4 solutions,respectively.Experimental results demonstrated that the antibacterial properties and corrosion resistance of the steel improved with the increase of Cu content.When Cu content was increased to 1.34%,the pitting corrosion of the steel in the SRB-inoculated medium was almost suppressed.The protective corrosion products formed in the sterile medium and antibacterial Cu ions continuously released from the steel in the SRB-inoculated medium resulted in the remarkable corrosion resistance of Cu-bearing pipeline steels.

关 键 词：微生物腐蚀 硫酸盐还原菌 含Cu管线钢 抗菌性能 耐蚀性能 

分 类 号：TG174.2[金属学及工艺—金属表面处理]