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Plating/Coating Chemistry

 

Where can I find the chemical composition of various platings and coatings; for instance, zinc phosphate, iron manganese phosphate, zinc with yellow dichromate, etc. I have to report the percentage of each element to a customers materials database. Thanks.

Jeff Colbert
Dana Corp - Fort Wayne, Indiana

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This question comes up once in a blue moon, and to do a good job, you will need some basic texts with a chapter on each coating or group of coatings.

It also doesn't hurt to search the literature for relevant articles which often have this kind of information.

Also, you will need the MSDS of each chemical used in your process, for instance, if your yellow chromate has chromic acid, sulphates, and nitrates in the formulation, then you will see that the gel usually contains some of all of these, plus trivalent chromium from the reaction with the zinc metal that is being treated, etc. (some of these have trace amounts of fluoride, it depends on how detailed you want to get). The more stuff you say is in your coating, the more questions you will get from your customer. It could get very tricky, I don't envy you. See if you can get someone else to do it, but I am afraid you are it.

It will take you a few hours to a few weeks to do a decent job.

Good luck,

  
Tom Pullizzi
Falls Township, Pennsylvania