Cl^-对X80管线钢在NaHCO3溶液中腐蚀性能的影响  

Influence of chloride ions on the corrosion resistance of X80 pipeline steel in NaHCO_3 solution

作　　者：梁平[1] 李晓刚[1] 杜翠薇[1] 陈旭[1] 张亮[1] 

机构地区：[1]北京科技大学材料科学与工程学院

出　　处：《北京科技大学学报》2008年第7期735-739,共5页Journal of University of Science and Technology Beijing

基　　金：国家科技基础条件平台建设项目(No.2005DKA10400);国家“十一五”科技支撑计划资助项目(No.2006BAK02B01)

摘　　要：采用动电位极化方法研究了在0.5mol·L-1NaHCO3溶液中Cl-对X80管线钢腐蚀行为的影响,并通过电容测量方法对其腐蚀机理进行了探讨.实验结果表明:Cl-使X80管线钢在0.5mol·L-1NaHCO3溶液中发生了点腐蚀,且随着溶液中Cl-含量增加,腐蚀坑的数量增多,腐蚀坑的直径增大,降低了X80管线钢的耐腐蚀性能.Mott-Schottky分析表明:随着溶液中Cl-含量增加,X80管线钢钝化膜内的施主密度随之增大,增加了X80管线钢钝化膜局部破裂和腐蚀萌生的潜在位置,从而使其耐腐蚀性下降.The influence of chloride ions （Cl^-） on the corrosion resistance of X80 pipeline steel in 0.5 mol·L^-1 NaHCO3 solution was discussed by potentiodynamic polarization technique, and the corrosion mechanism was investigated by capacitance The results show that C1^- enhances the occurrence of pitting corrosion of X80 pipeline steel in 0.8mol·L^-1 NaHCO3, and the density and size of corrosion pits increase with increasing Cl^- concentration. Mott-Schottky results indicated that the value of donor density of the passive film increases with increasing Cl^- concentration, which enhances the potential sites of film local breakdown and corrosion initiation. It is concluded that the addition of Cl^- decreases the corrosion resistance of X80 pipeline steel in 0.5 mol·L^-1 NaHCO3 solution.

关 键 词：X80管线钢 氯离子 耐蚀性 钝化膜 Mott-Schottky分析 

分 类 号：TG174.2[金属学及工艺—金属表面处理]