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Alternatives for zinc coating?

I am looking for a ultra thin protective coating with excellent wear and corrosion resistance(not zinc). I have started to look into PVD, hot and cold blacking systems. Is there another alternative to these processes? If so could someone give me a direction to look?

Thanks,

Lincoln Fox
- Frederic, Maryland
2002

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You didn't say what you have against zinc for your particular application. Zinc is inexpensive and provides cathodic protection. If cost is not a major problem and cathodic protection is not required, there is an almost endless list of alternatives. But neither hot nor cold blackening provide excellent corrosion reistance--they certainly don't compare with zinc.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002

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Blackening, either hot or cold, won't provide any wear or corrosion protection. Thin Dense Chrome (TDC also known by several proprietary names such as Electrolize or Armalloy) is thin (50 microinches) and provides wear protection due to its HRC 72 hardness. These chrome layers don't provide huge corrosion resistance. Electroless nickel might do the trick but it will take two tenths of a mil (0.0002") for even moderate protection.

Milt Stevenson, Jr.
Syracuse, New York
2002