氯盐环境中新型合金耐蚀钢筋Cr10Mo1的钝化行为  

Passive Behavior of New Alloy Corrosion Resistant Steel Cr10Mo1 in Chloride-containing Environment

作　　者：艾志勇[1,2] 孙伟[1,2] 蒋金洋[1,2] 麻晗 张建春 宋丹[1,2,4] AI Zhiyong SUN Wei JIANG Jinyang MA Han ZHANG Jianchun SONG Dan(School of Materials Science and Engineering, Southeast University, Nanjing 211189 Jiangsu Key Laboratory of Construction Materials, Nanjing 211189 Research Institute of Jiangsu Shasteel Iron and Steel, Zhangjiagang 215625 College of Mechanics and Materials, Hohai University, Nanjing 210098)

机构地区：[1]东南大学材料科学与工程学院,南京211189 [2]江苏省土木工程材料重点实验室,南京211189 [3]江苏省(沙钢)钢铁研究院,张家港215625 [4]河海大学力学与材料学院,南京210098

出　　处：《材料导报》2016年第15期92-99,118,共9页Materials Reports

基　　金：国家"973"计划(2015CB655100);国家自然科学基金(51278098;51308111);江苏省产学研联合创新基金(BY20130)

摘　　要：应用线性极化、电化学阻抗谱与电容电位法等方法对比研究了合金耐蚀钢筋Cr10Mo1和普通碳素钢筋在预含不同浓度(0mol·L^(-1)、0.1mol·L^(-1)、0.3mol·L^(-1)、0.6mol·L^(-1))氯盐的较低碱度(pH=12.5)模拟混凝土孔溶液中的钝化行为,利用XPS方法分析钢筋钝化膜组成结构,分析了氯盐作用下两种钢筋钝化行为变化存在差异的原因,揭示了合金耐蚀钢筋强易钝化机制。结果表明:在各氯盐浓度下,合金耐蚀钢筋均能良好致钝且钝化效果并无较大差距,而普通碳素钢筋随氯盐浓度增大钝化效果显著减弱,当氯盐超过一定浓度则几乎不钝化,甚至发生明显点蚀。Cr氧化物作为合金耐蚀钢筋钝化膜不同于普通碳素钢筋的关键成分,高浓度氯盐作用下仍可保持稳定并维持钝化膜层完整密实,从而使耐蚀钢筋呈现强易致钝特性。Passive behaviour of alloy corrosion-resistant steel Cr10Mo1,with plain carbon steel introduced for comparison,in low alkaline（pH=12.5）simulated concrete pore solutions with different chloride contents（0mol·L^（-1）,0.1mol·L^（-1）,0.3mol·L^（-1）,0.6mol·L^（-1））,was evaluated by various electrochemical techniques（linear polarization resistance,electrochemical impedance spectroscopy and capacitance measurements）.XPS was used to determine the chemical composition of passive films formed on the steels.The reasons for differences of the passivation evolution between the two steels under the action of chloride was analyzed,and the mechanisms of strong passivation behavior of the alloy corrosion-resistant steel was revealed.The results show that the alloy corrosion-resistant steel has good and almost similar passivity in solutions with different chloride concentration,while plain carbon steel has a signi-ficant decrease in passivity with the increasing chloride concentration.Passivation can hardly occure and pits appear when chloride concentration is above a certain level.Cr oxides,as the key components which just make the differences between the passive films on the alloy corrosion-resistant steel and plain carbon steel,can still remain stable and maintain the good density and integrity of the passive layer on the alloy corrosion-resistant steel under high chlorides concentration,which provides the alloy corrosion-resistant steel favorable passivation performance.

关 键 词：合金耐蚀钢筋 钝化行为 钝化膜 氯盐 

分 类 号：TQ172.1[化学工程—水泥工业]