Corrosive Electrochemical Behavior of Carbon Steel in Microbiological Medium

硫酸盐还原菌 (SRB)生长代谢 ,溶液pH值从 7.5下降到 5.8,并在碳钢表面形成生物膜 ,改变了生物膜下碳钢表面的微环境 ,促进碳钢点蚀的形成 .清除表面的腐蚀产物后 ,碳钢基体表面为分布不均匀的溃斑 ,发生严重的点蚀行为 .而SRB的活性和生物膜的结构诱发碳钢腐蚀的形成和生长 ,在微生物快速生长过程中出现明显的氢扩散电流峰 ,加剧碳钢的渗氢行为 ,采用电化学阻抗 (EIS)研究了碳钢在微生物腐蚀过程中生物膜的结构与腐蚀相应的变化关系Sulfate_reducing bacteria(SRB)grows and propagates, PH of the solution is dropped from 7.5 to 5.8,and forms the biofilms on carbon steel in culture medium.The micro_environment on the surface of carbon steel is changed under the biofilms,the factors accelerate the formation of the pitting corrosion. When the biofilm on carbon steel is cleaned out,the surface of carbon steel have the non_uniform pitting corrosion. The activity of SRB and the porous structure of biofilms induced the initiation and development of the pitting corrosion of carbon steel.The process of microbiologically induced corrosion(MIC) involves the development of SRB activity,which promotes the permeation of gydrogen into the carbon steel.The relation of the structure of biofilms and corrosion was also studied using electrochemical impedance spectroscopy(EIS).作者联系地址：清华大学核能技术设计研究院,华中科技大学化学系,华中科技大学化学系,华中科技大学化学系,华中科技大学化学系,清华大学核能技术设计研究院 北京100084 ,湖北武汉30074 ,湖北武汉30074 ,湖北武汉30074 ,湖北武汉30074 ,北京100084Author's Address: 1.Institute of Nuclear Energy TechnologyINET,Tsinghua University,Beijing 100084,China; 2.Chem.Dept.,Huazhong University of Science and Technology,Wuhan 4300