模拟冷却水中黄铜管耐蚀性影响因素的光电化学研究

Photoelectrochemical study of influencing factors on brass corrosion in simulated cooling water

针对模拟冷却水中各种离子对黄铜管的耐蚀性影响采用光电化学方法和交流阻抗法进行了研究。在模拟水中黄铜电极表面膜显示p-型光响应,光响应来自电极表面的Cu2O层,改变模拟水溶液中Cl-、SO42-和S2-浓度时,其表面膜的半导体性质仍为p-型,但阴极光电流峰值的大小会发生变化,阴极光电流峰值越大,其耐蚀性能越好。随着Cl-、SO42-和S2-浓度的增加,黄铜的阻抗逐渐增大,耐蚀性能提高,当Cl-、SO24-和S2-浓度分别高于49.92 mg/L、80.8 mg/L、10 mg/L时,黄铜耐蚀性能降低,腐蚀越严重。

The photocurrent response method and the AC impedance method were used to study influences of various ions on brass corrosion in the simulated cooling water. The brass electrode shows p-type photoresponse which comes from the Cu2O layer on its surface. The photoresponse still remains p-type with different concentrations of CI- , SO4^2- , and S^2- ions, but the value of the maximal cathodical photocurrent varies. With the increasing of CI- , SO4^2 - , and S^2- ions, the impedance of the brass electrode increases, and so does its corrosion inhibition ability. The degree of brass corrosion accelerated with concentration of CI- , SO4^2- , and S^2- beyond 49.92 mg/L, 80.8 mg/L, and 10 mg/L respectively.