未处理钢筋在模拟混凝土孔溶液中的早期电化学性能

Early Electrochemical Performance of Untreated Steel Bars in Simulated Concrete Pore Solutions

在钢筋表面进行了微观结构表征和分析后,采用线性极化法和电化学阻抗谱法对未经处理的钢筋试件在模拟混凝土孔溶液中的早期电化学性能进行了研究。结果表明:电化学方法能较好地表征HRB400型钢筋在混凝土模拟孔溶液中的早期电化学性能,能准确地表征钢筋试件完全钝化时的状态;钢筋试件钝化完全时,钝化膜组成为FeO、Fe(OH)_2、Fe_2O_3和FeOOH等。与预处理过的钢筋的钝化过程不同,钢筋试件的自腐蚀电位在钝化期内的变化过程可以近似用高斯函数来拟合。

Based on the microstructure characterization linear polarization(LP) and electrochemical impedance spectroscopy(EIS) were utilized to investigate the early electrochemical performance of steel bars in simulated concrete pore solutions. Results show that electrochemical measurements are effective in detecting the early electrochemical performance of HRB400 steel bars in the simulated concrete pore solutions and can accurately represent the state of passivation. When the steel bars are passivated completely, the passive films are composed of FeO, Fe(OH)2, Fe2O3 and FeOOH. The passivation process is somewhat different from that of the pretreated steel bars. The change process of the corrosion potential of the steel bars in the passivation period can be approximated by the Gauss function.