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Stainless steel, paint and corrosion

We are building a ship. Under the waterline we are told to use stainless steel. I know that embrittlement will occur due to hydrogen formation. My question is this: If I paint the stainless steel first, will corrosion still be in effect due to lack of oxygen? Will the fact that a painted s/s surface is deprived of oxygen therefore cause the s/s to corrode? So is s/s under water not painted as bad as s/s under water painted? All information would be highly appreciated

Brian Peterson
professional machine shop foreman - Abu Dharbi U.A.E.
June 9, 2011

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Brian,
In our experience stainless steel under water isn't in nearly as much trouble as stainless steel right at the water line. This is mostly because the iron needs both moisture and air to corrode. Coatings such as paint are another way to keep air and moisture off your metal, though there's less value in using stainless rather than plain old carbon steel if you're going to put a coating on it anyway.

Ray Kremer
Stellar Solutions, Inc.

McHenry, Illinois

July 6, 2011