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How much corrosion resistance from chromating nickel  

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Is there a commercially available chromate for bright nickel and is there any corrosion data to show how much corrosion resistance is improved.

Thomas Christian
chemist - Apex, North Carolina

To my knowledge you cannot do a chromate conversion coating on nickel. However, it would not surprise me to be advised that there is chromate in the tarnish-ban post treatments sometimes done on nickel. I think you should inquire of Technic or another supplier of nickel and electroless nickel post-treatments as to whether there is chrome in them and how long they can be expected to keep the nickel from tarnishing.

Ted Mooney, P.E.  finishing.com Brick, New Jersey

Could there be a confusion of terms and you are talking about real chrome, Thomas? G. Marrufo-Mexico

Guillermo Marrufo
Monterrey, NL, Mexico

The tendency for bare nickel to corrode will be reduced by a mere dip in ANY hex chrome containing solution including the rinse water following the zinc or aluminum chromate. This will not be a "conversion coating", but it will deter tarnish.

Robert H Probert Robert H Probert Technical Services Garner, North Carolina Editor's note:        Mr. Probert is the    author of Aluminum How-To / Aluminio El Como