| 配方类型： |
METAL TREATMENTS |
| 配方组成： |
ethylene diamine/120 ml/l
citric acid/90 g/l
M-nitrobenzene sulfonic acid (sodium salt)/90 g/l |
| 配制方法： |
the pH of the solution can be adjusted with ammonium hydroxide to a value of 10 electrometrically. the solution can be operated at a temperature of 60-65 C using a water bath.
in the aforementioned solution, the role or the nitro substiuted group is to oxidize the nickel and nickel-iron alloy surfaces. the organic amine functions as a comjplexing agent for the nickel ions and provedes a buffering action to stabilize the pH of the solution and, most importantly, is active in preventing the etching of the substrate which might be attacked by the nitro aromatic compound.
citric acid functions as a complexing agent for the oxidized nickel and iron. it helps to soluvilize the nickel and iron ions and assist in their quick removal form the surface of the deposit so htat the nitro compound can function efficiently. |
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