电力铁塔角钢镀锌层在NaCl介质中的腐蚀行为研究  

Corrosion Behavior of Angle Steel Galvanized Layer of Power Tower in NaCl Solution

作　　者：邱妮[1] 姚强[1] 苗玉龙[1] 宗庆彬[2] 黎学明[2] 杨萍[2] 

机构地区：[1]重庆市电力公司电力科学研究院,重庆401123 [2]重庆大学化学化工学院,重庆400044

出　　处：《表面技术》2011年第5期5-8,91,共5页Surface Technology

基　　金：重庆市电力公司重点科技项目(2010渝电科技30#);重庆市交通委员会科技计划项目;重庆市自然科学基金(2004BB6065)

摘　　要：采用Tafel直线外推法、加速腐蚀试验,研究了角钢镀锌层在NaCl溶液中的腐蚀行为,利用SEM和XRD表征角钢镀锌层的腐蚀形貌及腐蚀产物。结果表明:随着NaCl溶液温度和浓度升高,角钢镀锌层腐蚀电流密度增大;加速腐蚀试验的产物可阻碍Cl-腐蚀,使得角钢锌层的腐蚀速率随试验时间的延长而减小;锌层的氧浓差腐蚀为慢腐蚀过程,不易形成"蚀坑",而Zn-Fe构成原电池的腐蚀为快腐蚀,易造成表面的"蚀坑";锌层白色腐蚀产物主要是Zn5(OH8)Cl2.H2O。Corrosion behavior of angle steel galvanized layer was studied in NaC1 solution by Tafel linear extrapolation and accelerated corrosion test. Morphologies and corrosion products after corrosion were characterized by SEM, XRD. The results show that the corrosion current density of angle steel galvanized layer becomes larger when the solution temperature and the concentration of NaC1 increase. The products of accelerated corrosion test can provide protection against chloride corrosion, and the corrosion rate become smaller with the extension of test time. Oxygen concentration cell corrosion of zinc layer is a slow corrosion process that can not form ＂eclipse pits＂ easily, while the primary cell of Zn-Fe corrosion is a quick corrosion process that can result in superficial ＂eclipse pits＂ easily, and the white corrosion products are mainly Zn5 （OH）8CI2 · H2O.

关 键 词：电力铁塔 角钢 镀锌层 腐蚀行为 加速腐蚀试验 

分 类 号：TG174.3[金属学及工艺—金属表面处理]