论文部分内容阅读
利用极化曲线、交流阻抗谱、Mott-Schottky曲线分析、循环极化曲线的方法,研究了X80抗大变形(X80HD)管线钢在模拟土壤碱性腐蚀环境(0.5 mol/L Na2CO3+1 mol/L Na HCO3溶液)中的耐蚀性。结果表明,该钢在25~95℃范围内均会发生钝化现象,氧气不是钝化发生的必要条件;随着温度升高,钝化变得不稳定,自腐蚀电位减小,自腐蚀电流密度增加,电荷转移电阻减小,耐蚀性变差;25℃时,加入0.5%Na Cl未见明显点蚀,而加入1.5%Na Cl后发生了严重的点蚀,表面可见大量腐蚀坑的存在;一定程度上升高温度可以降低X80HD管线钢在添加Cl-的溶液中发生点蚀的可能性,这主要是由于升高温度,OH-浓度增加所致。
The effects of X80HD pipeline steel in simulated alkaline soil eroding (0.5 mol / L Na2CO3 + 1 mol / L) were studied by means of polarization curve, AC impedance spectroscopy, Mott-Schottky curve analysis and cyclic polarization curves. L Na HCO3 solution) corrosion resistance. The results show that the passivation of the steel occurs in the range of 25 ~ 95 ℃. Oxygen is not a necessary condition for passivation. With the increase of temperature, passivation becomes unstable and the corrosion potential decreases. The corrosion current The density increases, the charge transfer resistance decreases, and the corrosion resistance deteriorates. At 25 ℃, no significant pitting corrosion is observed when 0.5% NaCl is added, while severe pitting corrosion occurs after addition of 1.5% NaCl. A large number of corrosion pits There is a certain increase in temperature can reduce X80HD pipeline steel in the addition of Cl- solution pitting corrosion possibility, mainly due to increased temperature, OH- concentration increased.