Cl^-和SO_4^(2-)对模拟混凝土孔隙液中钢筋腐蚀行为的影响  

Effect of Cl^- and SO_4^(2-) on Corrosion Behavior of Reinforcing Steel in Simulated Concrete Pore Solutions

作　　者：易博[1] 林德源[2] 陈云翔[2] 戴念维[1] 杜旭辉[1] 张俊喜[1] 

机构地区：[1]上海电力学院上海市电力材料防护与新材料重点实验室,上海200090 [2]国网福建省电力有限公司电力科学研究院,福州350007

出　　处：《腐蚀科学与防护技术》2016年第2期97-102,共6页Corrosion Science and Protection Technology

基　　金：国家电网重点科研课题项目(gwkj2012-010-II-2);国家自然科学基金项目(50771062)资助

摘　　要：采用极化曲线和电化学阻抗技术研究了模拟液中Cl-/SO_4^(2-)比例及溶液浓度对钢筋在模拟混凝土孔隙液中腐蚀行为的影响。结果表明:当模拟液中m(Cl-)/m(SO_4^(2-))为1.5时,即溶液为亚氯盐渍土模拟液时,钢筋的腐蚀速率最大。钢筋的腐蚀速率随溶液中SO_4^(2-)含量的增加呈先增大后减小趋势,在模拟混凝土孔隙液介质中,一定含量的SO_4^(2-)会促进钢筋的腐蚀,而通过成比例增加溶液中SO_4^(2-)及Cl-的含量,模拟腐蚀的渐变过程,发现钢筋的腐蚀速率逐渐减小。电镜形貌分析进一步说明腐蚀速率的减小与钢筋电极表面盐膜形成而导致的阴极过程扩散阻力有关。The corrosion characteristics of reinforced steel in simulated concrete pore solutions with different amount of chloride ion and sulfate ion were investigated by means of polarization curves and electrochemical impedance spectroscopy. The results show that the corrosion rate of reinforced steel rose firstly and then declined with the increasing SO4^2-concentration in the solutions.The corrosion rate of the reinforced steel was the highest in a simulated sub-chloride saline soil solution（m（Cl^-） / m（SO4^2-）=1.5）. This suggested that addition of certain amount of SO4^2-can enhance the corrosion of reinforced steel. The corrosion rate of reinforced steel decreased gradually with the proportionally increasing amount of SO4^2-and Cl-in the solutions, which may be ascribed to the formation of a thick salt film on the steel surface and thereby lead to the increase of diffusion resistance for cathode process.

关 键 词：钢筋 模拟混凝土孔隙液 Cl^- SO4^2- 

分 类 号：O646[理学—物理化学]