特殊排水管道防腐保护层局部腐蚀原因分析及处理措施

Reason Analysis and Treatment Measures on Partly Corrosion of Special Drainage Pipeline

将排水管道用Q235低碳钢,在无氧条件下浸泡在NaHCO3溶液中,研究NaHCO3浓度对其极化曲线、开电位、电化学阻抗谱、腐蚀产物及其形貌的影响。结果表明,当碳酸氢钠溶液浓度高于0.02 mol/L时,Q235低碳钢表面被钝化,低于这个值时,Q235低碳钢将处于活性溶解状态。

The effect of NaHCO3 solution concentrations on polarization curves, open circuit potential, electrochemical impedance spectroscopy, and corrosion resistance of Q235 mild steel was studied by soaking in the NaHCO3 solution. The results show that the surface of Q235 mild steel will be passivated when the NaHCO3 solution concentrations is higher than 0.02 mol/L, and the steel will eventually be in active dissolution state below the value.