中文摘要：

研究了Na HCO3＋Na Cl碱性溶液中,较宽Cl^-浓度（0.001-0.3 mol/L）范围内Cl^-浓度及HCO3^-和Cl^-的浓度比值（[HCO3^-]/[Cl^-]）对Q235碳钢小孔腐蚀电位的影响。结果表明,Cl^-浓度较大（〉0.02 mol/L）时,碳钢的稳定孔蚀电位Eb和亚稳态孔蚀电位Em都与[HCO3^-]/[Cl^-]符合很好的线性关系,[HCO3^-]/[Cl^-]升高Eb和Em线性增大;当Cl^-浓度较小（〈0.02 mol/L）时,Eb和Em与[HCO3^-]/[Cl^-]之间不存在良好的线性关系,该条件下碳钢表面在发生稳定孔蚀前观察不到微米级的亚稳态小孔。

英文摘要：

The influence of Cl^-concentration and the concentration ratio of HCO3^-to Cl^-（[HCO3^-]/[Cl^-]） in Na HCO3＋Na Cl alkaline solution on the pitting potentials of Q235 carbon steel was studied in a chloride ion concentration range from 0.001 to 0.3 mol/L. It was found that when the Cl^-concentration is higher than 0.02 mol/L, good linear relationship exists not only between the pitting potential Eband [HCO3^-]/[Cl^-] but also between the meatstable pitting potential Emand [HCO3^-]/[Cl^-],that is Eband Emincrease linearly with the increase of [HCO3^-]/[Cl^-]. When the Cl^-concentration is lower than 0.02 mol/L, [HCO3^-]/[Cl^-] is not linear with Eband Em, and under these conditions, no micron scale metastable pits can be observed on the steel surface before the occurence of stable pits.