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Wanted: Non-conductive coating for tiny metal tubes

2004

I am trying to find a non-conductive coating/process for a metal (aluminum, Stainless steel, etc.) tube. The hard part is getting a coating that will uniformly coat the ID and edges of the tube. The tube ID is very small (.050 inches). The length of the tube is .650 inches. The OD is .060 inches.

The coating must be abrasive resistant, withstand up to a temperature of 175 °C, bondable using adhesives and biocompatible. I have looked into black hard anodizing and also a Kapton dip coating, but the edges and ID of the tube is not uniform and very spotty. Any help will be appreciated.

Thanks,

Kim Young
Medical Device Application - Watertown, Massachusetts, USA

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2004

Hi Kim,

An Epoxy based E-Coat may be what you are looking for.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

 

These requirements can all be readily met by a vapor-phase deposition process. We have several such processes that coat the inside, outside, and edges of small tubes with abrasion- and corrosion- resistant sub micron thick FDA compliant coatings that are are also excellent bases for adhesive bonding, painting, etc. Have you considered any such processes? Can you say anything more about the intended application?

Giles Dillingham, Ph.D.
- Cincinnati, Ohio, USA
2004

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Hi,

A new type of anodising coating called PEO coating [Plasma Electrolytic Oxidation] will give you a uniform non conductive oxide layer that does not depend on the morphology of the substrate. The coating thickness is 10-100 micrometers. The surface layer is rough making it suitable for adhesive bonding and paintings. The coating exhibits high value of hardness, wear and corrosion resistance in addition to excellent adhesion.

Katerina Plati
St John's College - Cambridge, UK
2004