十八烷基二甲基甜菜碱对冷轧钢在H2SO4溶液中的缓蚀性能

Inhibition Action of Dodecyl Dimethyl Betaine on Cold Rolled Steel in H2SO4 Solution

利用失重法、动电位极化曲线、电化学阻抗谱(EIS)、扫描电镜(SEM)和原子力显微镜(AFM)研究了十八烷基二甲基甜菜碱(BS-18)对冷轧钢在0.5 mol/L H2SO4溶液中的缓蚀性能。结果表明,BS-18对冷轧钢在0.5 mol/L H2SO4中具有优良的缓蚀性能,且BS-18在钢表面的吸附符合Langmuir吸附等温式。缓蚀率会随着温度的升高而增大,在50℃时BS-18浓度为100 mg/L时缓蚀率可高达96.9%。添加BS-18后同时抑制了阴极和阳极反应,使电荷转移电阻显著增大,且显著降低了冷轧钢表面的腐蚀程度实。

The inhibition action of dodecyl dimethyl betaine(BS-18) on cold rolled steel(CRS) in 0.5 mol/L H2SO4 solution was assessed by means of weight-loss measurement, potentiodynamic polarization technique, electrochemical impedance spectroscopy(EIS), scanning electron microscope(SEM) and atomic force microscope(AFM). Results indicate that BS-18 exhibits excellent inhibitive ability on CRS in 0.5 mol/L H2SO4 solution. The adsorption of BS-18 on CRS surface follows Langmuir isotherm. Its inhibition efficiency increases with the increase of temperature, and it can reach as high as 96.9% at 50 ℃ with 100 mg/L BS-18. With the addition of BS-18, both cathodic and anodic corrosion reactions are inhibited simultaneously, and the charge transfer resistance is drastically increased, which leads to that the corrosion degree of the cold rolled steel surface is significantly decreased.