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Stripping copper from Cobalt Chromium Molybdenum-Nickel

I have critical item with tight tolerances where the plating house was to make the part
and plate only a specific area on the OD of the part - well they plated the whole part!

Can you strip the copper plating without damage to the machined surfaces?

Gene Tarver
Program Mgr - Farmingdale, New York
September 3, 2010

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September 8, 2010

Dear Gene Tarver,

If you have the choice between throwing the part away and try this, I would first try this before throwing the part away:
I assume you're well aware of what chemistry and cyanides mean in handling.
Make a solution of 50g/l. KCN and 10 g/l. K2CO3 (Equivalent amounts in Sodium salts are OK as well), keep it at 15 - 25¿â°, place the product anodically at an average CD of 5 A/dm2, make sure that you have as much equidistances between product and anode as possible, agitation is required (stir the solution or move the product and check visually the progress of the stripping process every minute. (You will strip away app. 2u of Copper per minute.) There could be some attack of your alloy, but this will be minimal.

Success,

Harry van der Zanden
- Budapest, Hungary