高级检索

    交流干扰下纯锌在酸性红壤中的腐蚀行为

    Corrosion Behavior of Pure Zinc in Acidic Red Soil under AC Interference

    • 摘要: 通过静态腐蚀失重试验研究了10~100 mA/cm2交流干扰下纯锌在红壤中的腐蚀行为。采用失重法计算腐蚀速率,500 Hz数据采集卡连续记录电极电位,扫描电子显微镜观察试样表面形貌,能谱和X射线衍射仪分析腐蚀产物成分和物相。结果表明,施加10~100 mA/cm2交流电流干扰时纯锌腐蚀速率是未施加交流干扰时的3.243~9.675倍。通过法拉第定律,利用质量损失计算发生腐蚀的净法拉第电量,发现施加10~100 mA/cm2交流干扰时,产生的净法拉第效率仅为1.852%~4.783%。交流电流产生的阳极总电量与净法拉第电量之间具有强相关性。腐蚀速率vC与交流电流幅值(imax)符合关系式vC=2.880+0.071imax(10 mA≤imax≤100 mA)。纯锌腐蚀电位随腐蚀时间变化呈现出正弦曲线规律,变化幅值随交流电流密度增加而增加。与未施加交流干扰试样相比,施加交流干扰后纯锌腐蚀电位出现净负向偏移,偏移量随着交流电流密度增大而增大。施加交流电流干扰后,纯锌腐蚀加剧并诱发点蚀。在交流电流干扰24 h后纯锌表面腐蚀产物主要为ZnO、Zn(OH)2、Zn4Si2O7(OH)2和SiO2

       

      Abstract: The corrosion behavior of pure zinc in red soil under the interference of AC with current density of 10-100 mA/cm2 was studied through static corrosion weight loss test. The corrosion rate was calculated using the weight loss method, and the electrode potential was continuously recorded using a 500 Hz data acquisition card. The surface morphology was observed using a stereo microscope and scanning electron microscopy (SEM), while the composition and morphology of the corrosion products were analyzed using energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results show that the corrosion rate of pure zinc under an applied AC current of 10 mA/cm2 to 100 mA/cm2 was 3.243 to 9.675 times that without AC interference. By substituting the weight loss into Faraday's law to calculate the net Faraday charge of corrosion, it was found that the efficiency of net Faraday charge produced by AC interference of 10 mA/cm2 to 100 mA/cm2 was only 1.852% to 4.783%. There was a linear relationship between the total anodic charge produced by the alternating current and the net Faraday charge, and a relationship formula to estimate the corrosion rate through current density had been established, that was vC=2.880+0.071imax(10 mA≤imax≤100 mA). The corrosion potential of pure zinc exhibited a sinusoidal variation pattern, with the amplitude of change increasing as the AC current density increased. Compared to the corrosion potential of pure zinc, there was a net negative shift in corrosion potential, and this negative shift increased with the increase of AC current density. After applying the AC current, the corrosion traces on the surface of pure zinc became more severe and pitting was induced. After 24 hours of AC current interference, the corrosion products on the surface of pure zinc were ZnO, Zn(OH)2, Zn4Si2O7(OH)2, and SiO2.

       

    /

    返回文章
    返回