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How to depassivate?

1998

Hello,

I want to depassivate nickel plated accessories, I need to do this to change the color of the accessories, The goods are nickel plated and I replate them gold or Black nickel.

The accessories are passivated some of them over the time, and some of them with solutions.

If anyone can give information how to do this or, has another suggestions, I'll be thankful.

I hope my words satisfy your comprehension.

Thank you in advance

Joe tarnouz

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Proprietary nickel activators are available from several of the suppliers listed in our Chemicals Directory, but a generic Wood's Nickel Strike is fine a lot of the time.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1998

Very high nickel parts that have been baked at high temperatures are very hard to activate. Sulfuric acid with anodic/cathodic treatment is one standard. Sulfuric / htdrofluoric acid mixture with very little anodic current also might work. Mixtures of nitric and hydrofluoric works well for a dip only process. Ammonium bi fluoride is a much safer source of the fluoride ion. Nitric and hydrochloric acid mixtures will also work, but may have more of a tendancy to pit.

James Watts
- Navarre, Florida
1998