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Is zinc and clear coating RoHS compliant?

We are in a dilemna. We are a fastener distributor with tons of inventory that is commercial zinc and clear plated. Very little is zinc and yellow. Is our zinc/clear compliant with the RoHS European directive? No one can give us a straight answer. From what I read, the problem lies with the yellow and green chromates and not the clear.

Thank you for your help.

Tom Swiatkiewicz


Sell it quick to a different market. Even though clear, it is unlikely that it is RoHS compliant. Although trivalent chromating has existed as a process for many years, it was rarely used because of traditionally very poor corrosion resistance. As a rule of thumb, unless you have strong substantiation that the material is RoHS compliant it isn't.

Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey


Ted, I disagree with you -:)
For some years , people use trivalent chromates for clear passivation on zinc. A good trivalent based clear passivation has good corrosion resistance - 24-48 hours in NSS.
It is the iridescent trivalent that has corrosion problems and needs a sealer.
It is true that trivalent is not self healing like hexaalent, but yet it is used for some time.
You may ask your supplier what did he use or perform a test with diphenyl carbazide.

sara michaeli
sara michaeli signature
Sara Michaeli
Tel-Aviv-Yafo, Israel

I am working on converting our cameras to be RoHS compliant. There are a few mechanical parts left that are non-RoHS due to flash nickel plating. We have sent samples to all the companies we have found so far that do RoHS flash nickel plating, but we have been very unsatisfied with the results. We are still sending out samples but it is about time to have a plan B.

Most of the parts are copper (flash nickel plated) and used in heat dissipation. What could be a good RoHS alternative to flash nickel plating for these copper parts (or, what is the closest RoHS plating to flash nickel)?

We are considering RoHS zinc plating, but one of the parts is used in a vacuum package and I could not find the outgassing rates of nickel and zinc plating.

I am not a mechanical engineer so I would really appreciate any kind of input.

Thanks and regards.

Sa'ed Abu-Alhaija


I don't understand why the flash nickel parts are not RoHS complaint. What is the issue?

Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey

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