通过动电位极化曲线、电化学阻抗潜以及Mott—Schottky曲线的测试,研究了预钝化电位对模拟混凝土孔溶液中钢筋的钝化作用及氯离子对钢筋钝性的影响.结果表明,在室温下相对于饱和甘汞电极电位为-0.200—0.200V范围于不同电位分别预钝化4800 s后,钢筋表面均处于钝态;钝化膜内浅层施主浓度随预钝化电位的升高而减少,深层施主浓度则增加;预钝化电位为0.200 V时,钢筋钝化膜的电荷转移电阻最大;预钝化后的钢筋在含氯离子0.01—0.08 mol/L,pH值为12.50的模拟混凝土孔溶液中浸泡24h后,其表面钝化膜表现为高掺杂的n型半导体,在0.15—0.47 V电位区间内表现为一种类型的施主浓度,施主浓度随氯离子浓度的升高而减小.Potentiodynamic anodic polarization,electrochemical impedance spectroscopy and Mott-Schottky plot were used to study the effect of passive potentials and chloride ion concentrations on the corrosion behavior of reinforcing steel in simulated concrete pore solutions.The results indicated that the compact passive films were formed on the reinforcing steel surface at different passive potentials from -0.200 to 0.200 V vs SCE for 4800 s,with increasing the potential the superficial donor densities decreased but the deep donor densities increased,and the charge transfer resistance of the film reached the highest value at the passive potential 0.200 V.Immersed in simulated concrete pore solutions with chloride ion concentration 0.01—0.08 mol/L and pill2.50 for 24 h,the passive film still behaved as n-type semiconductor,only one type of donor appeared from the Mott Schottky plot,and the deep donor densities decreased with increasing chloride ion concentration.国家自然科学基金项目20473066;; 国家重点基础研究发展计划项目2005CCA06700;; 福建省自然科学基金项目E0210006资助~
