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High coefficient of friction material

High coefficient of friction material

High coefficient of friction material

  Looking for a material that has a high coefficient of friction ( >.5) and is capable of withstanding very infrequent high energy stops (3ms duration with 1000W/in^2 energy at surface every 2 seconds).  Temperature of rotor rises to about 100F from room temp under heavy use.
   Currently, we are running vs. a low carbon steel rotor (this could be changed as well) with a number of different rubber compounds.  The rubber friction is not staying stable and I'm looking for a new class of material to try.  Any ideas?

RE: High coefficient of friction material

Look at the materials used on race cars. There is a new material(Ceramic) that  can take about any thing you throw at it.  There are a lot of Carbon based materials used.  There are several in the metallic category.

There are a lot of racing fans looking at this site maybe one will jump in.
What configuration is your braking system?

Here is list of some of the available brake pad materials.

RE: High coefficient of friction material

unclesyd...  Thanks for the input.  I have been thinking about this type of material, but I need higher coefficient than what is listed on the materials in your link.  The reason I need the high coefficient is that the pressure I can apply to the surface is limited by the rest of the mechanism and I can't increase the diameter because of space constraints.  Trying to find a material that works within all of our constraints is my main problem...  All help is appreciated.

RE: High coefficient of friction material

I would query some of the manufactureres of the high performance materials and see if they have anything in the pipeline that might work.

Also check the NASA site as the have done considerable work on brake materials.

Here is the website for high performance brakes


RE: High coefficient of friction material

Try lead, its .95, or copper.

RE: High coefficient of friction material

Try SGL Carbon in Germany. The deliver the brake discs for the Porsche 911 in carbon reinforced silicon carbide

RE: High coefficient of friction material

I would recommend a High Performance Polymer Bearing Material; ie. PEEK Bearing Grade COF of around .23, also we have PPS materials at .40 and Polyimide with COF in the .19 to .20 range all material have compressive values of 30K +.

Check out <www.aptechno.com>; we specialize in Polymer Bearings.

Bill V.

RE: High coefficient of friction material

For help you I need to know the following:
What are the overall dimension of your disc, diameter (inner outer diameter) and thickness, is vented o solid?
What type of assembly is used to fit the disc to the shaft?
You use a mechanical or hidraulic caliper?
If is hydraulic what are the maximum pressure in the system?
If is mechanical what is the maximum lenght that you are able to use in the arm load?
What is the max. shaft speed?
Do you know what desceleration you want to hold during the stops?
Variation in torque will be an issue for your application?
Do you know the maximum torque the machine is able to generate?
With this information I will be able to understand better your problem and recomend something to you.



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