Teflon Impregnation and Wear
Q. Does Teflon-impregnated aluminum offer a higher resistance to wear or corrosion? T.S.
A. Thanks for your question. It’s one that is often asked. You don’t specifically say, but I assume you mean anodized aluminum. There seems to be ongoing disagreement about Teflon impregnation of the anodic coating. Some folks will not concur with my answer to your question.
The term “Teflon impregnated” is actually a misnomer. Technically speaking, it is not possible to impregnate Teflon into the pores of the anodic coating. The Teflon molecule is too large to fit into the anodic pore. Some anodizers add a water-based Teflon emulsion to the anodizing bath. When parts are anodized in this bath some of the Teflon particles become trapped in the coating as it forms, but from what I have witnessed in the form of photo-micrographs only a few particles are involved. Yes, you might get the benefit of a few Teflon particles’ lubrication affect as the anodic coating gradually wears away, but to my knowledge it’s not really of much benefit.
I believe that the best and most common sense way to mate anodic coatings and Teflon is to coat the anodized parts with a dip or spray-on Teflon emulsion after anodizing and sealing. This coats the parts with a very thin film of Teflon that will help make the part very slippery and may give it some added corrosion protection. Depending on the application, the Teflon film will wear away over time. Teflon emulsions and other similar dry film lubricants are available in many formulations. The one I like best for many end use applications is a product called Vydax. It is a solvent-based Teflon emulsion that can be applied by dipping or spraying on the parts.
You don’t mention what your application is so I am not able to address it specifically.
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