pH值变化对B30铜镍合金腐蚀电化学行为的影响

Influence of pH on Electrochemical Behavior of 70/30 Cu-Ni Alloy

采用电化学阻抗谱、动电位极化曲线等电化学测试方法,研究了NaCl(质量分数为3.5%)溶液中pH值变化对B30铜镍合金腐蚀电化学行为的影响。结果表明:随着溶液pH值升高,B30材料的腐蚀行为由均匀腐蚀变为点蚀;材料阻抗值和瞬时腐蚀速率提高,极化电流密度降低;材料发生点蚀的倾向增大。

Influence of pH on electrochemical behavior of 70/30 Cu-Ni alloy in 3.5 % NaCl solution was studied by electrochemical impedance spectroscopy and potentiodynamic polarization. The results showed that the alloy corrosion resistance increases, polarization current reduces and the corrosion is controlled with the increasing pH of the solution. The oxide film could not form on the surface of the alloy and the corrosion is severe when the pH under3; corrosion can be controlled by the formation of the oxide film when the pH of the solution is in the range of 5-9; corrosion can occur when the pH exceeds 12.