シアン化銀めっき浴の厚付け特性
1988 年 39 巻 1 号 p. 34-39
詳細
1988 年 39 巻 1 号 p. 34-39
Characteristics of silver cyanide baths for heavy electrodeposition were studied in terms of bath composition, cathodic polarization curves and the appropriate range of current densities.
It was found that cathodic overpotential increased with increases in the content of potassium carbonate, and increased remarkably with the addition of 5g/L of potassium hydroxide. The addition of more than 20g/L potassium hydroxide, however, reduced the cathodic overpotential.
When silver cyanide and potassium cyanide consentrations were both higher, there was a wide range of appropriate current densities. The addition of potassium hydroxide raised the covering power, and also increased the range of appropriate current densities. Potassium carbonate also broadened the range of appropriate current densities.
Using a bath composed of AgCN: 125g/L, KCN: 180g/L KOH: 20g/L and K2CO3: 20g/L and a current density of 2-3 A/dm2, it was possible to obtain silver deposits of 2700μm or more.
