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Electropolishing formulations

 

Well we are an acid copper plating unit doing job work & on the lookout for electropolishing of SS for small complicated shape items that don't yield to mech. polishing. Kindly suggest to me a suitable low cost bath at room temperature.Your kind advice is eagerly awaited.

N. ARUN - Trichy, India

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The Electroplating Engineering Handbook has all sorts of formulations for you, with some of their advantages and disadvantages. Just stay away from perchloric acid.

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

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You are unlikely to find a room temperature, low cost solution. The room temperature solutions I have experimented with have a very narrow band of usable current densities and are very difficult to design good cathodes for.

The most common chemistry is a phosphoric acid, sulfuric acid mix but this works best at temperatures of 110° F plus. This may be OK if you live in Delhi during August but for most of us that is not room temperature. This solution will attract water from the air if you keep it at room temperature. In time this will degrade the performance of your bath. In the monsoon this could be a big problem. You will need to keep the bath heated to drive off the excess moisture. Good luck in your search.

John Holroyd - Elkhorn, Wisconsin