氧化硫硫杆菌和芽孢杆菌协作下Q235钢腐蚀行为

Corrosion behavior of steel Q235 co-influenced by Thiobacillus thiooxidans and Bacillus

采用表面分析技术、失重法和电化学测试技术研究了Q235钢在氧化硫硫杆菌(T.t,Thiobacillus thiooxidans)和芽孢杆菌(Bacillus)协同作用下的腐蚀行为.扫描电镜结果表明,与单菌体系相比,混菌体系会形成最为致密的生物膜;混菌体系中浸泡的试样表面会出现不同于单菌体系的圆形蚀坑.腐蚀失重结果表明,混菌中试样的腐蚀速率介于2个单菌体系之间.交流阻抗结果表明,混菌体系浸泡2天后试样表面出现2个时间常数,表面膜层电阻经历了先增大后减小的过程.

Surface analysis methods, a mass loss method, and electrochemical tests were employed to in vestigate the corrosion behavior of steel Q235 under the synergistic effect of Thiobacillus thiooxidans （ T. t） and Bacillus. Scanning electronic microscopy （SEM） results reveal that a densest biofilm was formed in the mixed bacteria culture; The surface of the sample immersed in the mixed culture appeared circular corrosion poles which much different from the ones in the singlebacteria cultures. Mass loss method results indicate that the corrosion rate in the （T. t）Bacillus system was between the singlebacteria system. Electrochemical imped ance spectroscopy （EIS） show that there were two time constants existed in the T. tBacillus system after 2 d immersion, the corrosion resistance of the film performed as initially enhanced then weakened.