Local Corrosion Behavior of 316L Stainless Steel Studied by Scanning Electrochemical Microscope
-
摘要: 通过电化学试验获得316L不锈钢在NaCl溶液中的动电位极化曲线,确定了特征电位;采用扫描电化学显微镜研究了不锈钢在NaCl溶液中不同特征电位下的局部腐蚀行为。结果表明:在开路电位(-0.1 V)下极化后,面扫描图像中未见明显的电化学活性点,基底背景电流变化较小,钝化膜具有较好的稳定性;在自腐蚀电位(-51.2 mV)下极化后,面扫描图像中存在一个电化学活性点,但峰值电流降低,基底背景电流稳中有降,不锈钢发生自钝化;在典型钝化电位(100 mV)下极化后,表面发生亚稳态点蚀的不断萌生与钝化,基底背景电流先降低后保持稳定,表面自钝化程度更高;在点蚀电位(568 mV)下极化后,表面出现稳态点蚀坑,极化停止后点蚀坑被钝化,基底背景电流较极化前下降,表明未发生点蚀处钝化膜的稳定性增强。Abstract: The potentiodynamic polarization curve of 316L stainless steel in NaCl solution was obtained by electrochemical test, and the characteristic potential was determined. The local corrosion behavior of stainless steel at different characteristic potentials in NaCl solution was studied by scanning electrochemical microscope. The results show that after polarization at the open circuit potential (-0.1 V), no obvious electrochemical active point was found in the surface scan image, and the substrate background current changed little, indicating good stability of the passivation film. After polarization at the self corrosion potential (-51.2 mV), there was an electrochemical active point in the surface scan image, but the peak current decreased and the substrate background current was stable with a slight decrease, indicating the existence of self passivation behavior in stainless steel. After polarization at a typical passivation potential (100 mV), the surface underwent continuous initiation and passivation of metastable pitting; the background current of the substrate first decreased and then remained stable; the degree of surface self passivation was higher. After polarization at the pitting potential (568 mV), steady-state pitting pits appeared on the surface, and after polarization stopped, the pits were passivated; the substrate background current decreased compared to that before polarization, indicating an enhanced stability of the passivation film in the non-pit areas.
-
-
[1] ZHANG Q H,LI X R,LIU P,et al.Quantitative study of the kinetics of hydrogen evolution reaction on aluminum surface and the influence of chloride ion[J].International Journal of Hydrogen Energy,2021,46(80):39665-39674.
[2] 刘增威.SECM对7075铝合金在NaCl溶液中的电化学腐蚀行为研究[D].赣州:江西理工大学,2017. LIU Z W.Electrochemical corrosion behavior of SECM on 7075 aluminum alloy in NaCl solution[D].Ganzhou:Jiangxi University of Science and Technology,2017.
[3] ZHANG Q H,LIU P,ZHU Z J,et al.Quantitative analysis of the polarization behavior of iron in an aerated acidic solution using SECM[J].Electrochemistry Communications,2018,93:143-147.
[4] INDIRA K,NISHIMURA T.SECM study of effect of chromium content on the localized corrosion behavior of low-alloy steels in chloride environment[J].Journal of Materials Engineering and Performance,2016,25(10):4157-4170.
[5] ASSERGHINE A,MEDVIDOVI AC'G -KOSANOVI AC'G M,NAGY L,et al.In situ monitoring of the transpassivation and repassivation of the passive film on nitinol biomaterial by scanning electrochemical microscopy[J].Electrochemistry Communications,2019,107:106539.
[6] LI X R,ZHANG Q H,MENG X Z,et al.Effect of pretreatments on the hydrogen evolution kinetics of pure titanium using impedance and SECM technologies[J].Corrosion Science,2021,191:109726.
[7] SIMOES A,BATTOCCHI D,TALLMAN D,et al.Assessment of the corrosion protection of aluminium substrates by a Mg-rich primer:EIS,SVET and SECM study[J].Progress in Organic Coatings,2008,63(3):260-266.
[8] 周亚茹.电沉积Ni金属涂层和Ni-P合金涂层失效过程的宏观-微区电化学比较研究[D].杭州:浙江大学,2016. ZHOU Y R.Macro-micro electrochemical comparative study on failure process of electrodeposited Ni metal coating and Ni-P alloy coating[D].Hangzhou:Zhejiang University,2016. [9] XIA D H,WANG J Q,WU Z,et al.Sensing corrosion within an artificial defect in organic coating using SECM[J].Sensors and Actuators B:Chemical,2019,280:235-242.
[10] 舒明勇.选钛尾矿制备搪瓷涂层及腐蚀电化学行为研究[D].上海:上海大学,2019. SHU M Y.Preparation of enamel coating from titanium tailings and its corrosion electrochemical behavior[D].Shanghai:Shanghai University,2019.
[11] IZQUIERDO J,MARTÍN-RUÍZ L,FERNÁNDEZ-PÉREZ B M,et al.Scanning microelectrochemical characterization of the effect of polarization on the localized corrosion of 304 stainless steel in chloride solution[J].Journal of Electroanalytical Chemistry,2014,728:148-157.
[12] LISTER T E,PINHERO P J.The effect of localized electric fields on the detection of dissolved sulfur species from type 304 stainless steel using scanning electrochemical microscopy[J].Electrochimica Acta,2003,48(17):2371-2378.
[13] 李桐.医用高氮无镍奥氏体不锈钢在仿体液中的腐蚀电化学研究[D].济南:山东大学,2018. LI T.Corrosion electrochemical study of medical high nitrogen nickel-free austenitic stainless steel in simulated body fluid[D].Jinan:Shandong University,2018. [14] 刘增威.SECM对7075铝合金在NaCl溶液中的电化学腐蚀行为研究[D].赣州:江西理工大学,2017. LIU Z W.Electrochemical corrosion behavior of SECM on 7075 aluminum alloy in NaCl solution[D].Ganzhou:Jiangxi University of Science and Technology,2017.
[15] 石林,郑志军,高岩.不锈钢的点蚀机理及研究方法[J].材料导报,2015,29(23):79-85. SHI L,ZHENG Z J,GAO Y.Mechanism and research methods of pitting corrosion of stainless steels[J].Materials Review,2015,29(23):79-85.
计量
- 文章访问数: 3
- HTML全文浏览量: 0
- PDF下载量: 3
下载:
