Sheet in PTFE CP20 1200x1200 mm natural

PTFE CP20 is a carbon-filled PTFE with about 20 percent carbon mixed in. Compared with CP15 you go one step further in mechanical reinforcement without losing what makes PTFE useful, the chemical resistance and the temperature range. The sheet therefore handles higher surface pressure and dynamic loads, which makes it a common choice for demanding sliding surfaces.

In terms of temperature the material works continuously up to around 260 degrees and takes deep cooling down toward cryogenic levels. The fire rating is V0 according to UL 94, the same as for other PTFE-based materials. The density is somewhat above pure PTFE because the carbon filling is heavier than the base matrix.

The chemical behavior stays essentially unchanged compared with unfilled PTFE. Acids, bases and organic solvents pass without attack; only molten alkali metal and elemental fluorine are real exceptions. Water absorption is negligible and the outgassing in vacuum is close to zero, which makes the grade suitable for clean environments as well.

What makes CP20 special compared with CP15 is the wear profile. The compressive stiffness is higher, the tendency to creep lower and the wear against steel is reduced further. For a designer that means a slide strip or a sealing lip in CP20 holds its dimensions longer under constant load, and that you can work closer to the theoretical PV limit of PTFE without risking cold flow.

In sheet, PTFE CP20 is often used as:

slide plates in heavy lift tables, carts and mold tools;

wear strips in presses and tipping devices with poorly lubricated contact surfaces;

gaskets in high-pressure couplings and flanges;

blank material for milled or turned bearing parts with tight dimensions.

Machining is done with ordinary carbide tools, but the carbon filling makes the material more abrasive on the cutting edge than unfilled PTFE. Sharp tools and low feeds pay off. The sheet is tough and hates hard clamping points in the fixture; use broad support so that thin parts do not deform under the cut. Gluing calls for an etched surface or plasma treatment.

The stock range covers both thin sheets for gaskets and thick blocks for turned and milled parts. When choosing thickness you count in extra material for final cutting and flattening, because PTFE moves slightly when it is unloaded.

Are you wondering whether CP15 or CP20 suits your application best? Get in touch and we will go through surface pressure, speed and operating temperature together.