接地极Q235碳钢材料在上海土壤环境中的腐蚀行为

通过电化学阻抗 (EIS)、极化曲线、扫描电镜 (SEM)、能谱分析 (EDS) 和X射线衍射 (XRD) 等技术对接地极Q235碳钢材料在含不同盐分的上海地区土壤中的腐蚀行为进行了研究。结果表明,在不同盐分土壤条件下,Q235碳钢的阻抗均随着浸泡时间的延长出现先升高后平稳的趋势,腐蚀速率随盐分含量增大而增大。由于沿海土壤的侵蚀性阴离子含量较高,使得所产生的锈层失去保护性。Q235碳钢腐蚀主要以全面腐蚀为主,还伴有微生物腐蚀现象,腐蚀产物膜主要由Fe₂O₃组成。根据耐腐蚀性能评价标准,接地极碳钢材料在上海土壤环境中的耐腐蚀性能为良。

Corrosion Behavior of Q235 Carbon Steel for Grounding Grids in Soil at Shanghai District

The corrosion behavior of Q235 carbon steel for grounding grids in artificial soils was studied by EIS, polarization curve measurement, SEM, EDS and XRD. These artificial soils were admixture of typical soil from the Shanghai free trade zone with different amount of salt, aiming to simulate the corrosivity of various soils of the entire Shanghai area. It is shown that with the increasing time, the corrosion impedance of the buried Q235 carbon steel increases firstly and then tends to be stable in soils with different salinity, its corrosion rates increases with the increasing salt content. The Q235 carbon steel suffered mainly from uniform corrosion accompanied with microbial corrosion, its corrosion products consisted mainly of Fe₂O₃. According to the evaluation criteria for corrosion resistance, the corrosion resistance of Q235 carbon steel for grounding grids in Shanghai soils can be ranked as fine.