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  for Metal Finishing since 1989
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Removing zinc from stainless steel

I have a zinc plated part that consists of steel and stainless steel. I wish to remove the zinc from stainless steel area.

I would like to know is there a reliable method to clean it. Also, there is a discolor zinc boundary on steel, around the contact area between the two materials. Is this going to continue to contaminate the part, even if zinc has been removed from the stainless steel? Thank you! HL

Hung Le
- Canada
2000

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Try any acid, diluted, but avoid halogenic acids, i.e., fluoboric, chloric, iodic etc. Rinse well. Suggestions: nitric, sulfuric, phosphoric, acetic.

The zinc will likely protect the steel from corrosive oxidation as long as good contact is maintained between the metals; when the zinc is gone, expect the steel to be affected. The zinc will certainly discolor as it is consumed, and many of the compounds which are formed when zinc is corroded are at least partly water soluble, so staining of the steel at the boundary is likely. Most, if not all of the zinc compounds you are likely to run into are white; as the zinc is consumed the colors turn more orange and red from the iron oxides and salts.

Dale Woika
SCSC - Bellefonte, Pennsylvania
2000