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-----How to compute the removed metal by electropolishing given the current and time
I am researching on electropolishing process and want to find out how to compute the removed metal given the applied current and dipping time. Can you provide the formula?
Jury Casasemployee - Cebu, Philippines
2007
Hi, Jury. What books do you have available for your research? Maybe we can point you to appropriate chapters. But start with Faraday's Law of Electrolysis -- it is most of the answer.
Ted Mooney, P.E.
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2007
Jury
How accurately do you want the answer? Faradays law is a good first guess but there could be purely chemical reactions, giving a higher rate of dissolution and/or other electrolytic reactions slowing the process.
Why not... Take a piece of metal, electropolish it, note the current and time and re-weigh it.
If you want to really understand the process repeat with new and old solutions, higher and lower currents / temperatures, etc.
Geoff Smith
Hampshire, England
2007
Geoff has the right idea. Electropolishing is not a very efficient process, so although Faraday's laws do apply (as they do to virtually all electrochemical reactions), the laws themselves will not give you an accurate answer with regard to metal loss. The problem is that not only is metal dissolved during electropolishing, but oxygen is discharged, so you need to take into account both processes. The best thing is to follow Geoff's advice and do a range of experiments under known conditions and find how the metal dissolution efficiencies vary with changes in experimental conditions
Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2007
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