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Possible Negative Effects of Exposure to Iron Phosphate Wash on Brass and Zinc-plated Forged Steel

I am designing a plugging device that will be exposed to a non-acidic iron phosphate wash. Would there be any problem with using brass and/or zinc-plated forged steel hardware in the design? Any degradation effects from an iron phosphate wash?

Thank you for your assistance.

Charisse Thomas
Engineer - Bonita Springs, FL, USA
December 8, 2008

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Hi, Charisse,

First, iron phosphate chemicals are acidic, which is mild corrosive as you have them in drum. After changing chemicals in you wash, the degree of its corrosion vary dependent on the way you run the wash in term of pH value. In general, the pH of tack solution is close to neutral, in which you may mean it is non-acidic. Here, you can use zinc-plated metal. Some just use mild steel.

Jun Zhang
- Cincinnati, Ohio
February 6, 2009