【摘要】 采用线性扫描伏安法和交流阻抗法研究了碳钢在不同实验条件下的腐蚀规律,碳钢在碳酸铵溶液中的阳极过程为溶解、钝化、过钝化溶解,溶解初期在电极界面的传质为线性扩散控制;随着溶液温度的升高,阻抗谱表示为单一时间常数的容抗弧,容抗弧直径逐渐减小,电阻变小,碳钢的腐蚀速度增大;Cl~-浓度越大,钝化区域变小,碳钢更容易腐蚀;加入硫脲缓蚀剂,碳钢容抗弧直径增大,电阻变大,有利于保护碳钢。更多还原

【Abstract】 The corrosion law of carbon steel under different experimental conditions was studied by linear sweep voltammetry and electrochemical impedance spectroscopy. The anodic process of carbon steel was dissolving,passivating and over passivating in ammonium carbonate solution. The mass transfer of the electrode at the initial phase was controlled by linear diffusion; with the increasing of solution temperature, the impedance spectrum was expressed as a single time constant. The diameter of reactance decreased gradually, the resistance became smaller and the corrosion rate of carbon steel increased. The greater the concentration of Cl~-, the smaller the passivation area,the corrosion of carbon steel increased. With the addition of the thiourea corrosion inhibitor, the increasing of the diameter of the reactance, the resistance became larger, which was beneficial to the protection of carbon steel.更多还原