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Reasons for Anode Polarization

Could someone share with me the reasons for anode polarization? Thank you.

Joseph S. Zhu
- Orange Park, Florida
1999
publicly reply to Joseph S. Zhu

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Polarization is a situation where the surface skin of a material will no longer dissolve into solution under the circumstances. It can be a good phenomena, for example: an anodic current is imposed on stainless steel electroless nickel tanks to prevent them from dissolving; the anodic film on titanium renders it resistant to corrosion when used as an anode basket, anodizing rack, etc.; anodiziation of aluminum is, in a way, a passivation process because the aluminum forms an oxide skin instead of dissolving into the bath.

Nickel anodes, and some other anode materials, will polarize if the current density is too high and/or there is no chloride in the solution or sulfur in the anodes.

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

I need more knowledge about the anode polarization and how to avoid the problem in electrolytic.

Sting Ning
- Luoyang, Henan, China
2003
publicly reply to Sting Ning