Chengtao LI
金属学报(英文版)
The corrosion behaviors of alloy 690 in 1 wt pct sodium hydroxide aqueous solutions with and without PbO were characterized by electrochemical measurements, including potentiodynamic polarization, electrochemical impedance spectroscopy and Mott-Schottky measurement. The results reveal that there is a great difference between the corrosion behaviors of alloy 690 in the two tested solutions. The corrosion current density in PbO-containing solution is higher than that in the solution without PbO, which may be attributed to the anodic dissolution of metallic lead deposited at the early stage of polarization. The electrochemical impedance of the specimen in PbO-free solution is higher than that in the solution containing PbO. The slope of the Mott-Schottky curve in Pb-containing solution decreases notably compared with that in the Pb-free solution, which can be interpreted by the chromium depletion in the duplex structure of passive films.
关键词:
Alloy 690
,
电化学阻抗谱
,
氧化铅
,
Mott-Schottky曲线
,
钝化膜
周欣
,
杨怀玉
,
王福会
腐蚀学报（英文）
利用动电位极化曲线、交流阻抗技术及MottSchottky曲线等方法,研究了钼酸钠对钢筋在5%NaCl混凝土模拟液中的电化学腐蚀行为和表面钝化膜性能的影响.结果表明：随钼酸钠浓度增大,缓蚀效率逐渐增加,对钢筋的腐蚀有较好地抑制作用,药剂在钢筋表面的吸附可有效屏蔽氯离子的侵蚀作用；Mott-Schottky结果表明,在-0.5~0.1 V SCE范围内,混凝土模拟液中钢筋表面钝化膜C-2sc-E曲线呈正线性相关,表明钢筋表面钝化膜为n型半导体,且随钼酸钠浓度增大,钢筋钝化膜载流子密度逐渐减小,钝化膜稳定性增强,耐蚀性逐步提高；钝化膜致密性分析表明,随钼酸钠浓度增大,钝化膜致密性增加,抗氯离子腐蚀能力增强.
关键词:
钼酸钠
,
steel rebar corrosion
,
corrosion inhibition
,
passive film
