不同晶粒度螺纹钢的电化学行为及其钝化膜的Mott-Schottky研究  

Electrochemistry Behavior of Rebars with Different Grain Size and Mott-Schottky Research of Passive Films

作　　者：罗检[1] 王毅[1] 蒋继波[1] 钟庆东[1] 朱振宇[1] 张磊[1] 

机构地区：[1]上海大学上海市现代冶金与材料制备重点实验室,上海200072

出　　处：《化学学报》2012年第10期1213-1220,共8页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.50571059;50615024);教育部新世纪优秀人才支持计划(No.NCET-07-0536)及教育部创新团队计划(No.IRT0739)资助项目~~

摘　　要：利用交流阻抗谱和极化曲线研究比较了四组不同晶粒尺寸的螺纹钢在模拟海水液(3.5%NaCl)中短期电化学腐蚀行为;利用硼酸缓冲液中钝化膜的Mott-Schottky理论比较了各试样在不同阳极极化电位下的钝化膜的优劣性.结果表明,在14 d的模拟海水短期浸泡期间,细晶粒螺纹钢在后期表现出较大阻抗值和较小的自腐蚀电流密度,耐蚀性能优于粗晶粒试样.在硼酸缓冲液中形成的钝化膜表现出典型的n型半导体性能,公共钝化区间为-0.15～0.8 V.在选取的-0.1,0.2,0.5 V三个不同极化电位下,细晶粒螺纹钢在硼酸缓冲液中的钝化膜稳定性、耐蚀性弱于粗晶粒螺纹钢.在0.5 V的外加电压下试样钝化膜的内层膜消失,钝化膜的施主浓度最低,膜最为致密、稳定.The effect of grain size on the electrochemistry behavior of rebars in 3.5% NaCl solution were investigated using electrochemical impedance spectroscopy（EIS） and polarization curves.The Mott-Schottky curves at different potentials were employed to compared the passive film formed on the rebars with different grain size.The results showed that fine-grained rebars had larger impedance value and less corrosion current density than coarse-grained rebars after immersed 14 d,and the corrosion resistance of fine-grained rebar was better.The passive film formed in borate buffer solution behaviored like a classical n-type semiconductor,and the passive ranges of the rebars were all between-0.15 and 0.8 V.The stability and corrosion resistance of the passive film formed on fine-grained rebars were worse than those of coarse-grained rebars at the potential of-0.1,0.2 and 0.5 V.The subcoat of the film vanished at the potential of 0.5 V.The donor densities was minimum,and the film was most compact and stable.

关 键 词：耐腐蚀 晶粒尺寸 螺纹钢 Mott-Schottky 

分 类 号：TG174.44[金属学及工艺—金属表面处理]