低合金钢筋在水泥萃取液中钝化膜的耐蚀机理研究  

Corrosion Resistance Mechanisms of Passive Films Formed on Low Alloy Rebar Steels in Liquor of Cement Extract

作　　者：刘明 程学群[3] 李晓刚[3,4] 卢天健[1,5] LILT Ming;CHENG Xuequn;LI Xiaogang;LU Tianjian(MOE Key Laboratory for Multifunctional Materials and Structures,Xi'an Jiaotong University, Xi'an 710049,China;State Key Laboratory for Strength and Vibration of Mechanical Structures,Xi'an Jiaotong University,, Xi'an 710049,China;Corrosion and Protection Center,University of Science and Technology Beijing,Beijing 100083,China;Ningbo Institute of Material Technology &Engineering,Chinese Academy of Sciences,Ningbo 315201,China;State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)

机构地区：[1]西安交通大学航天航空学院多功能材料与结构教育部重点实验室,西安710049 [2]西安交通大学机械结构强度与振动国家重点实验室,西安710049 [3]北京科技大学腐蚀与防护中心,北京100083 [4]中国科学院宁波材料技术与工程研究所,宁波315201 [5]南京航空航天大学机械结构力学与控制国家重点实验室,南京210016

出　　处：《中国腐蚀与防护学报》2018年第6期558-564,共7页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(51801149);中国博士后基金(2017M620448)~~

摘　　要：采用动电位极化曲线、Mott-Schottky结合XPS和AES,分析研究了Cr对耐蚀钢筋在水泥萃取液中形成的钝化膜的耐蚀机理。结果表明,随着浸泡时间的延长,钢筋电极的自腐蚀电流密度(Icorr)降低,浸泡1 d后可以形成具有保护性的钝化膜。Cr含量的增加减小了钢筋钝化膜中的载流子密度,提高了其稳定性。Cr含量的增加抑制了Fe2+向Fe3+的氧化过程,从而提高了钢筋钝化膜的耐蚀性。耐蚀钢筋中的Cr参与了钝化膜的形成,稳定钝化膜则主要由Fe的氧化物组成;钝化膜内层为含Cr-Fe的氧化物,外层为Fe的氧化物;钝化膜的厚度在3～4 nm之间,随Cr含量的增加而略微增大。Influence of Cr content on the corrosion resistance of passive films formed on low alloyed rebar steels in liquor of cement extract was studied by means of electrochemical techniques, X-ray photoelectron spectrometer and auger electron spectroscopy. The Icorrof steel electrodes is found to decrease with increasing immersion time, and protective passive films could form after 1 d immersion. The increase of Cr content decreases the carrier density of the passive films, thereby improves their stability.The increase of Cr content inhibits the oxidation process of Fe2+to Fe3+, thus enhance the corrosion resistance of the passive films. Stable passive films are primarily consisted of iron oxides with a thickness of3~4 nm. As Cr is involved in the formation of passive films, which induces the formation of an inner layer of complex Cr-Fe oxides beneath the outer layer of Fe oxides. The film thickness slightly increases as the content of Cr increases.

关 键 词：耐蚀钢筋 钝化膜 Mott-Schottky X射线光电子能谱 俄歇电子能谱 

分 类 号：TG172[金属学及工艺—金属表面处理]