ABSTRACT

In this study, the corrosion behavior of X60 was investigated in the presence of a mixed culture of sulfate-reducing bacteria (SRB) and iron-reducing bacteria (IRB) via weight loss, electrochemical impedance spectroscopy (EIS), and Tafel polarization techniques. Moreover, field emission scanning electron microscope (FESEM) images and X-ray diffraction spectrometry (XRD) were used to study the morphological changes of the surface of X60 and the composition of corrosion products after exposing X60 to the abiotic and biotic systems. EIS result confirmed the occurrence of microbial corrosion in the presence of SRB and IRB. In the exposed coupon to the mixture of bacteria, the result illustrated that the existence of IRB promoted the SRB growth, so corrosion rate increased compared to the exposed coupon to SRB and IRB, respectively. The mixture of SRB and IRB showed a synergistic effect and enhanced the pitting corrosion on the surface of X60.

摘要

在这项研究中，通过失重、电化学阻抗谱 (EIS) 和 Tafel 极化技术研究了在硫酸盐还原菌 (SRB) 和铁还原菌 (IRB) 混合培养物存在下 X60 的腐蚀行为。此外，利用场发射扫描电子显微镜 (FESEM) 图像和 X 射线衍射光谱 (XRD) 研究了 X60 暴露于非生物和生物系统后 X60 表面的形态变化和腐蚀产物的组成。EIS结果证实了在SRB和IRB存在下微生物腐蚀的发生。在暴露于细菌混合物的试样中，结果表明 IRB 的存在促进了 SRB 的生长，因此与暴露于 SRB 和 IRB 的试样相比，腐蚀速率分别增加。