利用极化曲线、电化学阻抗、扫描电镜和表面能谱等方法,研究了硫酸盐还原菌对X70钢在土壤中宏电池腐蚀的影响.结果表明,接菌或灭菌粘土和砂土组成的宏电池,砂土中试样为宏电池的阴极,粘土中试样为阳极;随实验时间的增加,接菌及灭菌粘土中自然埋藏X70钢腐蚀速率逐渐减小,而砂土中宏电池阳极的腐蚀速率一直相当高;接菌土壤宏电池的电流和电动势比灭菌的大,接菌及灭菌粘土中阳极的腐蚀速率分别是自然腐蚀速率的4.93和2.45倍;在宏电池阴阳极面积比15∶1情况下,接菌及灭菌粘土中宏电池阳极的腐蚀速率分别为宏电池阴阳极面积比1∶1时的5.01及2.33倍.
The effects of SRB on macrocell corrosion of X70 steel in soils were studied by using polarization curve technique, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and EDXA. It was noted that the SRB obviously affected the macrocell corrosion behavior of X70 steel. When X70 steel formed a macrocell between inoculation SRB or bactericide clay and sand, X70 steel in clay was an anode, while that in sand was a cathode. Along with test going, the corrosion rate of X70 steel, which was buried by natural style,was slow, but the anode of macro cell kept a rapid corrosion rate. The corrosion rate of X70 steel in clay was faster than that in natural condition. Current density and electromotive force of macro cell of X70 steel formed between inoculation SRB clay and sand was much larger than that between bactericide clay and sand. The corrosion rate of anode in inoculation SRB clay was 4. 93 times of that in natural condition. The corrosion rate of anode in bactericide clay was 2. 45 times of that in natural condition. When the area ratio of cathode to anode being 15:1 ,the corrosion ratio of anode in inoculation SRB clay and bactericide clay were respectively 5.01 and 2.33 times respectively of that in condition of the area ratio of cathode to anode baing 1:1.