[neilep (OP)]

What's the most frictionless material ?

What applications is it used for ?

[Karen W.]

Maybe silk?

[Karen W.]

When you said material you did mean Fabric didn't you?

[neilep (OP)]

When you said material you did mean Fabric didn't you?

I was actually thinking of harder substances but as I am Mr Ambiguity I suppose the word 'material ' can mean anything ...including fabrics !

[Karen W.]

When one sews at least in my neck of the woods we refer to fabric as material..LOL I kinda thought you might have meant something different! like maybe polished marble or really stainless steel!

[paul.fr]

how would you test the friction of the material? if you rubbed or ran it over another material, then the surface of that other material would interact with the original naterial. (how many times did i use the word, material?)

what about the answer being a train.

[lightarrow]

What's the most frictionless material ?

What applications is it used for ?

As paul.fr wrote, friction is a property of *two* materials, not one only; furthermore, it also depends on the physical properties of the surphaces which come in contact.

If, instead, you were talking about "viscosity" of a fluid, that is, the "inner" friction of a fluid when parts of it moves with respect to other parts, then the less viscous materials are "superfluids": no friction at all!

For example, if you pour 1 litre of superfluid liquid helium in a container which has on its bottom a slit as tiny as 1 mm X 0.001 mm, you loose your 1 litre liquid in a fraction af a second!

Other Very strange properties of superfluids from Wikipedia:

One of the most spectacular results of these properties is known as the thermomechanical or "fountain effect". If a capillary tube is placed into a bath of superfluid helium and then heated, even by shining a light on it, the superfluid helium will flow up through the tube and out the top as a result of the Clausius-Clapeyron relation. A second unusual effect is that superfluid helium can form a layer, a single atom thick, up the sides of any container in which it is placed.

A more fundamental property than the disappearance of viscosity becomes visible if superfluid is placed in a rotating container. Instead of rotating uniformly with the container, the rotating state consists of quantized vortices. That is, when the container is rotated at speed below the first critical velocity (related to the quantum numbers for the element in question) the liquid remains perfectly stationary. Once the first critical velocity is reached, the superfluid will very quickly begin spinning at the critical speed. The speed is quantized - i.e. it can only spin at certain speeds.

[paul.fr]

To elaborate on the train idea. which i previously forgot to.

I know it's not a material, which is the actual question. But i reckon a maglev train would produce very little friction.

[ukmicky]

What's the most frictionless material ?

Without being ambigous I think the anwser is probably Teflon which is Polytetrafluoroethylene (PTFE)

What applications is it used for

Many uses but have you fried anything lately []

[another_someone]

What's the most frictionless material ?

Without being ambigous I think the anwser is probably Teflon which is Polytetrafluoroethylene (PTFE)

What applications is it used for

Many uses but have you fried anything lately []

It's use expanded significantly with the advent of the nuclear industry (although that was more because of its chemical inertness than it lack of friction); it was then used to coat fishing lines; and only then did the French start using it to coat cooking dishes (the French did this rather than the Americans because the French did not have the FDA to deal with - the French could just do it without any regulation, while American companies would have had to prove its safety first, and no-one wanted to pay for that).

[peopleunit]

Don' know which one would be at the top of the list, but I imagine powdered graphite would be high on the list.

Thanks for mentioning super fluids... learned yet something else worthwhile today.

Naked Scientist... porn and science, shouldn't I be wearing rubber gloves or something as I type this? :-)

[Bored chemist]

Wet ice on wet ice also has a pretty low coeficient of friction.

[another_someone]

Wet ice on wet ice also has a pretty low coeficient of friction.

But are you not confusing lubrication with low friction solid materials.  I accept that the original question had some ambiguity in the matter, but the two things are, as far as I am aware, very different things.

[Soul Surfer]

It depends on the application for example if two surfaces are rubbing together and bearing a load its usually best to have one very hard smooth surface and one slightly soft and slippery one that's the way car big end bearings and metal plastic bearings work  for light loads like whatch gear wheels very strong hard substances and minimising contact area like jewelled bearings are best.  for simple flat surfaces just introducing simple rollers can reduce the friction way below any rubbing surfaces so roller and ball bearings are probably the ultimate for very high loads although high pressure liquid bearings or even magnetically operated ferrofluids are another way of doing this.

[Bored chemist]

OK, fair enough. Polished steel on ice also has a very low coeficient of friction. (And don't get me started onthe idea that the pressure under ice-skates melts the ice.)