Microbial corrosion of high manganese austenitic steel by a sulfate reducing bacterium dominated by extracellular electron transfer and intergranular effect

作者：Zixuan Xu, Tingyue Gu, Yunhu Ding, Renyang He, Yi Fan, Tiansui Zhang, Huihai Wan, Ying He, Yunqing Xiong, Hongfang Liu · 发表于：Corrosion Science · 年份：2025 · DOI：10.1016/j.corsci.2025.112799 · 被引用次数：19 · 研究领域：Corrosion Behavior and Inhibition、Hydrogen embrittlement and corrosion behaviors in metals、Metal Extraction and Bioleaching

Microbiologically influenced corrosion (MIC) of high manganese steel (25Mn) by a marine sulfate reducing bacterium (SRB) was systematically investigated. Mn² + enhanced SRB activity by H ₂ S detoxification. The culture medium with low carbon source increased MIC by 2.1 times. 4 % Cr in 25Mn provided partial passivation . Riboflavin and nano-magnetite injections validated the dominant contribution of extracellular electron transfer mechanisms. Electron backscatter diffraction showed the intergranular corrosion at austenite boundaries. SRB enhanced hydrogen permeation and decreased tensile strength by 21 %. This study identifies the primary mechanism of 25Mn and provides important insights into material design and corrosion mitigation.