海洋假交替单胞菌Pseudoalteromonas lipolytica分泌黑色素加速316L不锈钢腐蚀机理的研究  

Corrosion Behavior of 316L Stainless Steel in Media Containing Pyomelanin Secreted by Pseudoalteromonas lipolytica

作　　者：郭娜 毛晓敏 惠芯蕊 郭章伟 刘涛 GUO Na;MAO Xiaomin;HUI Xinrui;GUO Zhangwei;LIU Tao(College of Ocean Science and Engineering,Shanghai Maritime University,Shanghai 201306,China)

机构地区：[1]上海海事大学海洋科学与工程学院,上海201306

出　　处：《中国腐蚀与防护学报》2022年第5期743-751,共9页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(41976039,42006039和51901127);上海市自然科学基金(19ZR1422100)

摘　　要：以海洋假交替单胞菌P.lipolytica的野生菌株(WT)与产色菌株(∆hmgA)为模式菌株,重点研究海洋细菌分泌黑色素加速不锈钢腐蚀的行为和机理。通过扫描电镜(SEM)、激光共聚焦显微镜(CLSM)、X射线衍射(XRD)和电化学等手段证明了WT菌株不会造成不锈钢腐蚀,不锈钢在含WT的培养液中依然会形成完整的钝化膜;而∆hmgA菌株会在分泌黑色素的同时,在不锈钢表面形成矿化位点,从而破坏了不锈钢表面的钝化膜,造成严重的点蚀。不锈钢在细菌黑色素提取液中也会形成点蚀,但由于没有细菌参与,不锈钢的钝化膜相对完整,因此点蚀程度较轻。本文研究在含有产色细菌和黑色素物质的环境条件下不锈钢的腐蚀机理以及黑色素对钝化膜形成和点蚀发展的影响机制,从而丰富和拓展产色菌和细菌色素对金属腐蚀的机理。By taking marine Pseudoalteromonas lipolytica(P.lipolytica)wild type strain(WT)and the genetically engineered P.lipolytica mutant strain with hmgA gene deletion(∆hmgA)as model strains,the influence of marine bacteria secreting pyomelanin on the corrosion behavior of 316L stainless steel in marine bacteria culture solutions was studied via electrochemical measurements,scanning electron microscopy(SEM),laser confocal microscopy(CLSM)and X-ray diffraction(XRD).It was proved that WT strain did not cause corrosion of the stainless steel,correspondingly a compact passivation film may form on the steel surface in the medium containing WT.While the∆hmgA strain will secrete pyomelanin and induce formation of mineralization sites on the stainless-steel surface,thus destroying the formed passivation film and further causing serious pitting corrosion.In bacterial pyomelanin solution,the stainless steel will also be suffered from pitting corrosion,however,a rather intact passivation film can still be formed on the steel surface due to that no bacteria may be involved to the process.In general,this study revealed that the corrosion mechanism of stainless steel in the environments containing pigmented bacteria and the influence of pyomelanin on passivation film formation and pitting development.

关 键 词：海洋假交替单胞菌 产色菌 细菌色素 不锈钢 点蚀 

分 类 号：TG174[金属学及工艺—金属表面处理]