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  for Metal Finishing since 1989
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EN plating qualify

How can we decide on the plating thickness required with respect to the function or the environment. Can we have some eg. In case I have a component which will be under normal environment/ Or in case where is extremely exposed to air and moisture. In the above cases, What should be the plating thickness? What should be the percentage of Phosphorous? How do we qualify the plating process? What is the exact method to check for the corrosion resistance? Some types of test we are aware of is Nitric acid dip test, Ferroxyl test, plating thickness test, bend test, thermal test etc. Which of these should be applicable?

Sanjeeva.K
- Mysore, Karnataka, India
2003

Of course you understand there are numerous variables that control corrosion phenomena, but if you need corrosion protection you must start specifying high Phos EN (above 10%P) which is amorphous, hence much more resistant to attack for it has no grain boundaries where corrosion can start. Then, according to your substrate material and environment you can specify 0.0003" (which in my opinion would be a practical minimum for the more noble substrates such as copper or brass) for moderate service and up to 0.003" or more for severe exposure and more active substrates such as carbon steel. The later combination can pass a 1000+Hr salt spray test.

Guillermo Marrufo
Monterrey, NL, Mexico
2003