著者

井上 博之 山川 宏二 近藤 哲也 正木 征史

出版者

The Surface Finishing Society of Japan

雑誌

表面技術 (ISSN:09151869)

巻号頁・発行日

vol.41, no.11, pp.1178-1180, 1990-11-01 (Released:2009-10-30)

参考文献数

8

被引用文献数

2 4

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Silver deposits formed on copper substrates by replacement reactions show poor adhesion, and a silver film plated on such a deposit dose not adhere. Silver ion makes a highly stable complex with cyanide ion, so that in a silvercyanide solution, the activity of silver ion is very small. This is one of the reasons for the universal use of cyanide baths in the industrial silver plating.However, consideration of the difference between the values of the stability constants for the silver-iodide complex and for the copper-iodide complex suggest that the rate of replacement deposition of silver on the copper substrate in silver-potassium iodide solutions, might be comparatively low. To confirm this, the rate of replacement deposition of silver in a silver-potassium iodide solution (AgNO3 0.10mol/L, KI 2.00mol/L) and in a strike silver plating bath (AgCN 0.028mol/L, KCN 1.15mol/L) was estimated from the current density corresponding to the point of intersection of the anodic and the cathodic polarization curves. These estimated values were almost the same, and it is suggested that the silver-potassium iodide solution is not only a cyanide free silver plating bath capable of employing a copper substrate but a silver plating bath which requires no strike plating.

著者

西村 六郎 八木 雅之 山川 宏二

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.45, no.11, pp.1186-1191, 1996-11-15 (Released:2009-06-03)

参考文献数

7

被引用文献数

1

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The effects of carbon dioxide on corrosion rate, polarization curve and hydrogen content have been investigated for carbon steels in acetate solutions and sodium carbonate solution with a pH range of 2 to 9 at 313K under carbon dioxide and nitrogen atmospheres. In the acidic solutions less than pH4 both general corrosion and hydrogen content are accerated by the existence of carbon dioxide. In the solutions more than pH7 little corrosion is observed with or without carbon dioxide, where as hydrogen content is detected only at the existence of carbon dioxide. The anodic and cathodic polarization curves with or without carbon dioxide show that their reaction overpotentials are affected by carbon dioxide, effect of which changes depending upon pH. The results obtained are qualitatively explained in terms of the formation of iron carbonate, the adsorption of carbonate ions and so on.