Effect of SRB on the corrosion behavior of X100 steel was studied by measuring the growth curve in the process of sulfate reducing bacteria growth,solution state parameters,corrosion potential,electrochemical impedance spectroscopy and polarization curve.The results show that the growth cycle of SRB in seawater can be divided into the three stages of rapid growth,stable and decline stage.The change of S2-concentration and oxidation reduction potential depend on the number of the active SRB.The corrosion potential of X100 steel first decreases,then increases,and finally decreases with increasing immersion time.However,EIS results show that the corrosion rate of the X100 steel in seawater with SRB first increases,then decreases,and finally increases again with the increase of immersion time.Corrosion current density and corrosion rate of the X100 steel in seawater with SRB are lower than that in sterile seawater.Because the biofilm in seawater with SRB can prevent the sample from contacting with seawater directly,corrosion rate of X100 steel is inhibited.%通过测定海水溶液中硫酸盐还原菌(SRB)生长曲线、溶液状态参数、自腐蚀电位、电化学阻抗谱和极化曲线的变化规律,研究了SRB的存在对X100钢在该体系中的腐蚀行为的影响.结果表明:SRB在海水培养基中的一个生长周期可分为快速生长阶段、稳定阶段和衰亡阶段.溶液S2-浓度和氧化还原电位与SRB数目密切相关,X100钢的自腐蚀电位随时间增加呈现先负移、然后正移、最后负移的变化规律;EIS结果表明,在接菌海水中,X100钢的腐蚀速率随着浸泡时间的增加呈现先增大、后减小、再增大的变化趋势;与灭菌海水中的腐蚀相比,X100钢在接菌海水中的腐蚀电流密度降低,腐蚀减弱,其原因是SRB生物膜的存在阻碍了海水与试样表面的直接接触,从而抑制了金属的腐蚀.
展开▼
