摘要
通过引入硫酸盐还原菌(SRB)来改善AZ91镁合金在含氯离子溶液中的腐蚀情况.发现:镁合金在无菌和含菌介质中的腐蚀均为点蚀;当Cl-含量低于1.5 g/L时,含菌和无菌试样表面仅出现微小的点蚀坑,两种试样的腐蚀速度相差不大,说明在低Cl-含量的溶液中,SRB对镁合金腐蚀的影响作用不大;当Cl-含量高于1.5g/L时,两种试样表面的点蚀坑扩展,腐蚀速度随着Cl-浓度的增加而增大,且含菌试样的腐蚀速度要明显低于无菌试样,腐蚀电流密度和腐蚀电位随着Cl-浓度的增加而分别增大和降低,说明在高Cl-含量的溶液中,SRB生物膜的存在显著地降低了镁合金对Cl-的腐蚀敏感性.
Sulfate-reducing bacterium （SRB） was used to restrain the corrosion of AZ91 magnesium alloy in the solution containing chlorine ions, and a pitting corrosion was observed in both the sterile and the SRB samples. The results show that, when Cl^- content is less than 1.5 g/L, the two samples are of almost equal corrosion rate and possess only tiny pits on their surfaces, meaning that SRB only has slight effect on the corrosion of magnesium alloy in the solution with low Cl^- content. However, when Cl^- content is more than 1.5 g/L, the pits on the sample surfaces extend, and both of the corrosion rates increase with Cl^- content, especially the sterile sample. In addition, with the increase in Cl^- content, the corrosion current of SRB sample increases, while the corrosion potential decreases, thus coming to the conclusion that the existence of SRB biofilm greatly weakens the corrosive sensitivity of magnesium alloy to Cl^-.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2008年第7期92-96,共5页
Journal of South China University of Technology(Natural Science Edition)
基金
吉林省科技发展重点项目(20040315)
关键词
镁合金
氯离子
微生物腐蚀
硫酸盐还原菌
magnesium alloy
chlorine ion
microbiologically-influenced corrosion
sulfate-reducing bacterium
