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I need a chemically en wear resistant coating for nickel

In one of the process steps of a new process, that we are developing, we need to coat a nickel plate with a chemically and wear resistant coating. The coating should not contain any (heavy) metals. The layer thickness should be as small as possible (not exceeding 10 microns) The chemical environment is largely water with some formic acid (pH=2). Does anyone have suggestions for a suitable coating? How can I improve adhesion of the coating onto the Nickel?

Glenn Rexwinkel
- Netherlands
1999

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I sort of doubt if you will find an excellent answer.

A spray and bake Teflon coating is going to be very thin, less than 0.0004". Most spray on coatings are going to have at least a few microscopic bubbles, which will be a prime source for attack on the nickel.

A thin coating of Teflon will lower the coefficient of friction, but certainly would not qualify as a wear coating.

Grit blasting the surface with fine grit will improve the adhesion of any spray on coating.

There may be a PVD coating like titanium nitride that could have a chemical resistance to Formic Acid, but it is so unusual that corrosion testing has not been done. Possibly a thin layer of the equivalent of diamond by PVD might do.

James Watts
- Navarre, Florida
1999

Look into Diamond-like-carbon (DLC) coating for your application.

Mandar Sunthankar
- Fort Collins, Colorado
1999