52053

Wear resistant, low-friction coefficient coating for a cryogenic application

May 5, 2009

I need to identify a wear resistant, low-friction coefficient coating for a cryogenic application (as low as -280F). The moving part is made of 17-4PH stainless steel and is coated with Teflon. The corresponding mating surface is also 17-4PH SS with an electroless Ni coating. Currently the Teflon wears away after a few months/years of service. A suitable solution may include coating both surfaces or just one. The two surfaces are in a low velocity, low amplitude and low frequency sliding wear type application.

Anand Samant
User of plated components - Buffalo, NY, USA

Teflon is a generic name for a number of fluorocarbon products. Possibly there is another one out there with better wear characteristics and still will stand the low temp and the temp changes.
UHMW Polyethylene is great, but it depends on glue which I doubt will function long at that temp. I like chrome, but not at this temp. I would try one of the vapor deposition products such as titanium nitride (TiN).
A thought, can you go to micro roller bearings? Some of these are really small and good.

James Watts
- FL

NASA uses sputter-deposited molybdenum disulfide for lubrication in space, where temperatures can be very, very low.

Jim Treglio
- San Diego, California