采用电化学方法和表面分析技术研究了A3钢在链霉菌(Stremptomyces)和氧化亚铁硫杆菌(Thiobacillus fer-rooxidans,T.f)单独及共同作用下的腐蚀行为.结果表明,试样在不同的含菌腐蚀体系中浸泡7d后,表面生成了不均匀的生物膜层,并表现出各不相同的形貌特征;A3钢在氧化亚铁硫杆菌和链霉菌单种菌作用下发生了局部腐蚀,而混合菌体系中的试样发生均匀腐蚀;混合菌体系中A3钢的腐蚀失重速率介于两种菌单独存在时的腐蚀失重速率之间;试样浸泡14d后的电化学阻抗谱(EIS)测试结果表明,A3钢电极在氧化亚铁硫杆菌-链霉菌混合菌体系中的阻抗值介于两种单菌腐蚀体系之间.以上研究结果表明,A3钢在链霉菌体系中腐蚀最重,混合菌体系其次,氧化亚铁硫杆菌体系中腐蚀最轻.
The electrochemical measurement and surface analysis methods were carried out to investigate the corrosion behavior of steel A3 in Thiobacillus ferrooxidans,streptomyces and T.f-streptomyces mixed colony systems.Results showed that asymmetric biofilms adhered on the surface of steel A3 after 7 days of exposure in different corrosive systems;pitting corrosion occurred on the surface of steel A3 after 7 days of exposure in T.f and streptomyce solutions,but an even corrosion appeared in T.f-streptomyces mixed colony solution;weight loss in the mixed colony system was between those caused by each individual microorganisms;the electrochemical impedance spectroscopy results indicated that the impedance value of steel A3 in the mixed colony system was the medium of those in T.f and streptomyces system.Above results revealed that the most serious corrosion occurred in the streptomyces system,secondly for the T.f-streptomyces mixed colony solution,and corrosiveness of the T.f solution was the lightest to steel A3.