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Electroless Black Nickel

2006

Dear all,

I would like to make an inquiry to you,that have you ever heard of instant black colour after EN plating?

Shall you give me an ans. soon cause it's actually urgent.

Thanks a lot for your help! I appreciate for your contributes made.

Ng Wee Chong
Plating - KL, Malaysia

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2006

You have blacken mid phosphorus type EN coatings by immersing them into 50% by volume nitric acid at ambient temperature for about 30 seconds after plating. Some other oxidizing solution will also blacken EN.

The acid blackens EN by etching a pattern of peaks and valleys into the coating. Thus, the black will be dulled if the coating is rubbed (which breaks the peaks) even by hand.

Ron Duncan [deceased]
- LaVergne, Tennessee
It is our sad duty to note Ron's passing on Dec. 15, 2006. A brief obituary opens Episode 13 of our Podcast.