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Zinc and trivalent + clear and seal salt spray protection level

 

I would like to know whether zinc & trivalent + clear & seal would be an adequate protection against a 240hr salt spray test. The solution being, dissolved sodium chloride in distilled or deionized water (concentration of 50g/l) Dissolved copper(II) chloride dehydrate in the salt solution (concentration of 0.26g/1) What level of corrosion would be expected?

Andy Reynolds
- Gloucestershire, UK

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Las 240 horas son a corrosión blanca o corrosión roja?

Miguel Angel Martín
surface finishing shop
Madrid, Spain

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Miguel is right, you need to define what you are looking for at 240 hours. First sign of corrosion? 5%, 10% surface corrosion? White corrosion or red rust? There are many different criteria people look for to say whether a part passes or fails.

Trivalent passivations sometimes have trouble meeting requirements for white corrosion. If you are looking for red rust, then you are probably safe. It will require testing in any case.

Tim Neveau
Rochester Hills, Michigan