
plating, anodizing, & finishing Q&As since 1989
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How to handling copper-plated parts to prevent oxidation
2003
I plated a steel with copper and placed it in the warehouse for two months. After the two months, the parts oxidized, giving a very poor surface finish. What measures do I need to take to prevent oxidation? What is the shelf life for copper plated parts?
Solomon Towouh- Addison, Illinois, USA
First of three simultaneous responses -- 2003
The shelf life of copper plated parts depends on the environment in which they are stored - marine, industrial, rural. I believe storage of copper in an atmosphere containing sulphur or sulfides should be avoided. For temporary storage, there are several good corrosion inhibitors available that can be applied by immersion or spray. There are also treated pads that emit an inhibiting vapor that can be put in close proximity with the parts.
Cheers,
- Brighton, Colorado, USA
Second of three simultaneous responses -- 2003
Untreated copper will oxidize fairly rapidly. You can get commercial anti-tarnish (benzotriazole) from many chemical vendors.

James Totter, CEF
- Tallahassee, Florida
Third of three simultaneous responses -- 2003
Copper in air just oxidizes, so you must put some kind of barrier down. Practically every plating supply house sells one or more products to prevent copper tarnish. You can get several months protection by just dipping in water that has been turned slightly orange with Chromic Acid.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

