Metal finishing Q&As since 1989

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Electropolishing for more than conventional amount of metal removal

2003

Hi,

Electro-polishing process typically removes the outer layer of the part about 1.5 - 2.0 ten thousandths . Can we control how much material will be removed by electropolish process if we knew an average roughness of part? (a tolerance is ± ten thousandth) for instance: if I want electro-polishing process removed 5 ten thousands of inch, what should the average roughness be?

Thank for your support,

Hieu Nguyen
biomedical- Denver, Colorado, USA

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I don't have specific experience in your exact problem, Mr. Nguyen, but I do have a piece of understanding that may help guide you. Electropolishing is very effective at removing burrs and asperities because these are high current density areas which will draw the electrochemical activity. But electropolishing is not necessarily effective at producing flat surfaces; rather a waviness can occur that can become more pronounced the longer you electropolish, rather than less. If you take some time to really think about it, you will realize that it isn't quite valid to consider the crests of such gentle waves as high current density areas that will be melted away.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003