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316 SS Electropolishing

What is the right process for the electropolishing (solution , Temperature and time) for 316 Stainless steel . I have few samples for lab corrosion test.
Regards

Saud Al Subai
Student - Manchester, UK
January 14, 2010

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Hi, Saud. Some people use straight sulfuric acid, most use phosphoric-sulfuric mixtures, many use proprietary acid or low acid processes. But there is a lot to it. The Electroplating Engineering Handbook [on AbeBooks or eBay or Amazon] has an excellent chapter that explains the bright range vs. the etching range, the importance of freedom from water, how parts must be racked because of the large amount of hydrogen generated, many different solution compositions, etc. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
January 14, 2010

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January 15, 2010

Saud, One of the important things about being a student is finding out where to find the information you require. The easy option is to ask someone for the answer, but this does not teach you h0w to source original information, which is a very important thing you should be capable of doing.

Electropolishing 316 stainless steel is very easy and can be done with a mixture of sulfuric and phosphoric acids. There is a great deal of literature on the subject as well as a plethora of sources where you can get electropolishing solutions from in the UK. However, each commercial solution will have its own operating conditions, so I suggest you buy some commercial solution and follow their instructions. If you want to make your own, do a literature survey on the different solutions and follow their optimised conditions. Good luck in your studies

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK