What Are The Four PEEK Grades?

Analysis of the high temperature performance, wear resistance and chemical resistance of PEEK materials - What are the four PEEK grades?

PEEK is available in generic and brand-specific grades; however, there are four main PEEK grades used throughout the industry:

1, Unfilled PEEK resin

2, 30% glass-filled PEEK

3, 30% carbon filled PEEK

4, Bearing grade PEEK (also known as PTFE PEEK, carbon fiber reinforced graphite PEEK).

The performance characteristics of PEEK materials:

1, PEEK plastic is characterized by its high-temperature performance, abrasion and chemical resistance, stability in aqueous environments, as well as excellent strength, toughness characteristics.

2, PEEK was invented for use in high-temperature environments, so it can be kept in operation at temperatures exceeding 500 °F. Even when melted.

3, PEEK also has lower smoke and toxic gas emissions and is less likely to catch fire. Compared to other plastics, PEEK has an excellent strength-to-weight ratio as well as the outstanding thermal conductivity and lubricity required for bearing applications. It has good abrasion and wear resistance as well as excellent fatigue, stress cracking and UV resistance.

4, PEEK is a tough material, but can still exhibit flexibility comparable to other plastics (but this is highly dependent on the particular PEEK grade).

5, PEEK's flexural modulus is closest to that of human cortical bone, which, coupled with its biocompatibility, makes PEEK an ideal choice for medical implants and devices.

6, PEEK is purely radiopaque (invisible under MRI, CT or X-ray scanners) and even resistant to gamma radiation.

7, PEEK is chemically resistant to almost all organic and inorganic chemicals, and is resistant to solvents, oxidation and acids.

The four main grades of PEEK materials:

1, Unfilled PEEK is the generic form of PEEK plastic, and therefore the most common grade. Unlike other grades, unfilled PEEK is very pure and is not reinforced with other components. Unfilled PEEK has the highest elongation, toughness (not to be confused with strength) and fatigue resistance of all PEEK grades. Unfilled PEEK meets FDA regulations and is approved for use in repetitive food contact and ex vivo medical applications. Unfilled PEEK is available in a variety of colors, but primarily white, light brown/tan and black.

2. 30% glass-reinforced PEEK, which reduces the expansion of PEEK and increases its flexural modulus. As a result, glass-reinforced PEEK is a stronger, stiffer version of the unfilled grades, making it ideal for structural applications where stability is required (especially in high-temperature environments). While glass-reinforced PEEK is stronger, it can be more abrasive when mated with other components.30% Glass-reinforced PEEK is available in natural/tan or black.

3. 30% Carbon Reinforced PEEK is impregnated with 30% carbon fiber, which increases its stiffness and compressive strength and significantly reduces its expansion rate. Carbon-filled PEEK is optimally formulated for wear resistance and load-bearing capacity, and its thermal conductivity is 3.5 times higher than unfilled PEEK. These properties make carbon-reinforced PEEK an ideal material for plastic bearings, and due to the introduction of carbon fibers, 30% carbon-reinforced PEEK is black in color.

4.Bearing grade PEEK varies from manufacturer to manufacturer, but is typically impregnated with 20% PTFE and graphite reinforced carbon fibers. Bearing grade PEEK has the lowest coefficient of friction and the highest machinability of all PEEK grades, as well as excellent wear characteristics in mating, friction, and load-bearing applications. For these reasons, this PEEK grade is designated as a "bearing grade" because it is ideal for bearings in a wide variety of industries. Bearing grade PEEK is typically gray or black in color.