Letter 2071

Corrosion resistant coatings under Sea water and temperature exposure conditions

--

I am looking for an alternate chrome coating or any thin coating on top of chrome that could resist corrosion in the sea water environment + temperature between 200-300 degrees centigrade.

I need point of contact for this information.

maroof qurashi
dept of navy - crane indiana

A coating referred to as diamond like nanocomposite thinfilms can resist corrosion of components working under sea water. It can withstand temperatures upto 400 degrees C. It is a thinfilm coating having high microhardness,low coefficient of friction,and low stress.

The thinfilm is wear resistant and self lubricating and the contact angle with water is very high. So for the application under consideration the material may work depending upon what part it is actually coating. The life of the part depends upon its use and certainly the environment.

Surajit Chatterjee -
Calcutta, India

Maroof, if you have a thin complementary metal in mind, or if you want us to try a metal like nickel, tantalum, etc., we are willing to look into it.

Mandar Sunthankar
- Fort Collins, CO

Maroof;

I have a great deal of experience with the use of TDC (Thin Dense Chrome) in some very hostile and corrosive environments. I'd be pleased to share this info.

Leslie Lenetsky

We appreciate your offer to help. Please remember that dozens of people read this pages, have seen Maroof's inquiry and, hopefully, have had their curiosity peaked. Please try to offer some additional technical info for public consumption. Thanks!

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

You did not state why you need chrome. Chrome is good for friction and wear but generally poor for corrosion protection because of its glavanic position and its tendency to microcrack. You can improve corrosion resistance by nickel plating under the chrome (better yet copper/nickel in the duplex approach...similar to the best steel auto bumbers ever made.

If the chrome is decorative consider modifying your esthetic point of view. If for corrosion resistance of steel, consider zinc-rich paint with a topcoat. If friction/lube consider dry lubes.

C.A.Smith
The Aerostructures Corp. Nashville, TN

I'm looking for a sprayed applied coating product that can coat a stainless steel metal working under sea water and can stand a temperature over 200 degrees centigrade.

Lucio Olaez
- Brampton, Ontario, Canada