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Calculation of contamination levels in trivalent chromating for zinc plating

How to calculate contamination in zinc trivalent passivation.

Ajay Goel
consumer - Delhi, India
2007

Ed. note: please use a few more words, Ajay, as people will be able to help you best if you describe your situation -- rack vs. barrel, acid vs. alkali, thin film vs. thick film, jobshop vs. captive, proprietary vs. homebrew, etc. Good luck.

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2007

Ajay,
While agreeing with the Ed. Note by Ted, I will answer your question in that sense.
First of all, Comparison in Tolerance to contamination level in trivalent passivation and intensity of problems due to this are now-a-days referred to sell competitive products.So you will have to know which of these product you are using and what is the claim by the supplier.Generally iron and Zinc in ppm level is considered contaminants.This can be analyzed by AAS (Atomic Absorption Spectrometer ⇦this on eBay or Amazon [affil links] ). This equipment costs between 8-15 lakh Indian rupees and small platers generally depend on supply houses or professional labs.
You have to be more elaborate and specific to get more detailed answers.
Regards

T.K. Mohan
plating process supplier - Mumbai, India