Anodic dissolution of brass and dezincing-resistant brass investigated using channel flow double electrode

作者：Hoshi Yoshinao^*; Itagaki Masayuki; Tabei Kozue; Shitanda Isao

来源：Journal of Solid State Electrochemistry, 2015, 19(12): 3551-3557.

DOI：10.1007/s10008-015-2840-9

• Copper
• Brass
• Dezincing-resistant brass
• Dezincification corrosion
• Channel flow double electrode
• Electrochemical impedance

The anodic dissolution mechanism of brass and dezincing-resistant brass in an electrolyte solution of 0.5 M NaCl containing 0.5 mM NaHCO3 was investigated using a channel flow double electrode (CFDE). CFDE is useful for investigating the anodic dissolution mechanisms of various metals because the valence of the ions dissolved from a metal working electrode can be determined by arranging a detecting electrode downstream from the working electrode. We measured the dissolution currents of cuprous ions (i (Cu(I))) and cupric ions (i (Cu(II))) during the measurement of the anodic polarization of brass and dezincing-resistant brass, from which we determined the potential ranges for the preferential dissolution of Zn (region (I)) and simultaneous dissolution of Cu and Zn (region (II)). The dissolution efficiency (I center dot (Cu)) was estimated using the anodic dissolution current of the working electrode (i (W)), i (Cu(I)), and i (Cu(II)), which was defined as the ratio of (i (Cu(I)) + i (Cu(II))) and i (W). I center dot (Cu) of brass at 0.1 and 0.2 V vs. SSE was low compared to the composition ratio of the Cu contained in the brass. This indicated that the dissolution of brass in region (II) was strongly related to the preferential dissolution of Zn from the brass surface. In contrast, the I center dot (Cu) of dezincing-resistant brass at 0.1 V vs. SSE was nearly identical to that at 0.2 V vs. SSE. This demonstrated that the simultaneous dissolution of Cu and Zn from the surface of dezincing-resistant brass occurred in region (II).

• 出版日期2015-12