Non-stick and adhesion properties of coatings

[qwerty]

Hello everyone,

I am searching for a coating/surface with good non-stick and wear properties. Adhesive tapes should not stick into the surface. I have found some commercial coatings that have hard thermally sprayed layer and top of it fluoropolymer kind of top-coat. Any other ideas about different kinds of coatings with similar properties?

I do not know how to measure the adhesion of the tape onto the surface. Is there somekind of standard test like ASTM for testing non-stick/adhesion properties of the surfaces?
Is the measuring of the coating's surface energy (measuring contact angle) the best way to evaluate non-stick properties or is there any other ways? Does the non-stick properties have something to do with the low-friction surfaces like PTFE?

I hope this makes sence and someone could help me. Thank you.

[Gordon]

Hi Qwerty

to the Surface Engineering Forum.

Quote:I am searching for a coating/surface with good non-stick and wear properties. Adhesive tapes should not stick into the surface. I have found some commercial coatings that have hard thermally sprayed layer and top of it fluoropolymer kind of top-coat. Any other ideas about different kinds of coatings with similar properties?

What are the specific coating functions, substrate and service environment conditions? There are few materials that show the same level of anti-wetting or non-stick properties of the fluoropolymers within certain operating conditions. The down side in many applications is that these materials are soft and have low wear resistance, hence usually some form of reinforcement in the form of composites or as you mentioned thermal spray coatings. The maximum service temperature of around 260 C while being very good for a polymer will be a limitation in some applications. I will also make the point that due to the high non-stick properties, these materials are also challenging to stick to substrates to form coatings

Quote:I do not know how to measure the adhesion of the tape onto the surface. Is there somekind of standard test like ASTM for testing non-stick/adhesion properties of the surfaces?

I'm not aware of any specific standard, though I think there are standards on measuring tape adhesion properties. Tape test is a simple and convenient way to demonstrate and maybe a qualitative comparison test of non-stick surfaces.

Quote:Is the measuring of the coating's surface energy (measuring contact angle) the best way to evaluate non-stick properties or is there any other ways? Does the non-stick properties have something to do with the low-friction surfaces like PTFE?

Yes. While low friction surfaces are often associated with non-stick properties, non-stick should not be confused with low friction; The two are different. Friction results from two surfaces moving across each other and is measured by a number that describes the drag (force) between them. Release is the property of a surface which results in the inability of substances to adhere or wet it. It is a function of surface energy that can be measured by the angle of contact between the surface and a drop of liquid. The larger the contact angle, the better the non-stick properties.

Ideally, testing should reflect the actual service conditions and be inclusive of other properties like wear resistance, corrosion, friction, strength, temperature etc..

[ives]

Well, the best thing that you can do right now is to for a tape test as it would really help you determine what kind of a non-stick you are having. If you are looking for a non-stick where adhesive tapes won’t stick, then most of the non-sticks out there could do that!