含硫酸盐还原菌土壤中阴极保护对Q235钢腐蚀的影响

利用交流阻抗测试技术、扫描电镜及表面能谱、微生物分析等方法，研究了阴极保护对土壤中Q235钢硫酸盐还原菌腐蚀的影响.30天的实验结果表明，在相同的阴极极化电位下，有菌土壤中Q235钢所需要的阴极极化电流密度均大于灭菌土壤，有菌土壤中Q235钢的平均腐蚀速率均大于灭菌土壤.随着阴极极化电位负移的增大，有菌及灭菌土壤中Q235钢试件周围土壤逐渐呈碱性，有菌土壤中Q235钢试件周围土壤中硫酸盐还原菌数量逐渐减少，当阴极极化电位为-1050 mV时，Q235钢试件周围土壤中硫酸盐还原菌仍能够存活.

EFFECTS OF CATHODIC PROTECTION ON CORROSION OF Q235 STEEL IN SRB CONTAINING SOILS

The effects of sulfate reducing bacterial(SRB) on cathodic protection of Q235 steel in soils have been studied,using bacterial analyses,electrochemical impedance spectroscopy(EIS),scanning electron microscopy (SEM) and EDS.The results showed that with increasing applied cathodic potential,pH value of soil gradually increased,the number of SRB and corrosion rate of Q235 steel decreased,and cathodic protection efficiency increased.At a cathodic potential of-1050 mV,SRB could still survive in soil around the sample of Q235 steel.At the same cathodic potential,the cathodic protection efficiency in soil without SRB was higher than that with SRB,and the corrosion rate of Q235 steel in soil with SRB was obviously larger than that without SRB.At the same cathodic potential,the cathodic current density needed for Q235 steel in soil with SRB was also larger than that without SRB.