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Stainless steel electropolishing

2005

What would be used as a stainless steel electropolishing chemical?

In literature I found following materials;

phosphoric acid
chromic acid
sulfuric acid
perchloric acid
glycol
water

In the same time, their volumes in the mixture are not dedicated specifically. Is there anyone know how can we prepare the mixture?

Ayca CAKIR
Medical Device Production - Istanbul

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2005

Perchloric acid should not be used due to the extreme explosion hazard. Chromic acid should probably be avoided for environmental reasons unless it is proven to be needed. All of the other patented formulations (mostly expired) that you have found have enjoyed success and there is no way to say that you should accept one and dismiss the others as a general rule that applies to all situations.

But successful electropolishing usually requires development work by experienced people because agitation, control of water content, pretreatment, and current density are all significant factors to be tamed.

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

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2005

60% Phosphoric
30% Lactic
10% sulfuric

Do not allow water to get into the solution

Be careful when putting components in and out. When you do you need to have the power switched off as the Hydrogen bubbles will ignite if a spark is created

Chris Matthews
- East Sussex, England

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75% phosphoric/25% sulfuric will also work. 100F, 50-150 asf.

Jeffrey Holmes, CEF
Spartanburg, South Carolina
2005