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Cr VI question

How I can identify the Cr VI on parts. Because In our factory we changing the ZN12C plating to Zn12B.

Ending our platings with B, does it possible we are free of Cr VI?

It be good if you can help me with this.

Thanks in advance.

Bst Rdgs,

Emanuel Aguilera
- SLP, SLP, Mexico
2005

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2005

Don't really know what your 'C' and 'B' designations are all about but suspect that they refer to colored vs. bright chromate. Fact is that most clear chromates, that is those used alone without a sealer which give moderate corrosion protection, do indeed contain significant amounts of hexavalent chrome, thus, are NON-RoHS ( & ELV, WEEE, etc.) compliant. There certainly are many newer trivalent chrome based post zinc plate bright dips that are compliant, provide 100+ hours of salt spray protection (even without a sealer!), etc.

Milt Stevenson, Jr.
Syracuse, New York

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Que tal Emmanuel,

I believe that B and C stands for a Valeo standard. You should check the standard.

Identifying Cr VI from Cr III, use the search engine in this site. One example comes in letter no. 32952

Saludos.

Guillermo Castorena
- San Luis Potosi, Mexico
2005