【摘要】 阴极保护数值模拟计算以实测极化曲线作为边界条件时,极化曲线能否正确反映金属表面的实际极化状态影响着数值模拟的准确性。对Q235碳钢新鲜和阴极保护5 d后的表面在自然海水中的交流阻抗进行了分析,确定了最大扫描速率,获得了更接近实际极化情况的曲线,得到了更理想的数值模拟结果。结果表明:测量极化曲线时能准确反映电极表面状态的最大扫描速率与极化电流相对误差、电压扫描范围成正比,与反应电阻和电容成反比;极化电阻和电容增大时,测量极化曲线的扫描速率相应成比例降低;最大反应阻抗时的电位为电极的最佳保护电位,该保护电位随保护表面的变化而变化,Q235碳钢表面沉积钙镁盐后,最佳保护电位正移。更多还原

【Abstract】 Alternating- current impedances of newly exposed Q235 carbon steel surface and the same steel surface after 5 d of cathodic protection in natural seawater were analyzed,and the maximum scan rate was determined.In the meantime,the polarization curves which could well refelect the real polarization state were obtained,and more satisfactory numerical simulation was acquired.It was found that the maximum scan rate of polarization curve accurately reflecting the state of the electrode surface was proportional to relative error of polarization current and scan range of voltage,and inversely proportional to resistance and capacitance of reaction.The scan rate declined proportionally with increasing resistance and capacitance.When reaction impedance was the greatest,the potential was the optimum protection potential which varied with varying state of the electrode surface,and it moved positively after calcium and magnesium salts were deposited.更多还原