How Effective is the Use of PEEK in 3D Printing?

What is Polyether Ether Ketone (PEEK)?

Polyetheretherketone (PEEK) is a colorless organic thermoplastic polymer belonging to the Polyaryletherketone (PAEK) series, which is used in engineering applications.

PEEK is a semi-crystalline thermoplastic plastic with excellent mechanical and chemical resistance that remains unchanged at high temperatures. The processing conditions for molding PEEK affect its crystallinity and hence its mechanical properties. Its Young's modulus is 3.6 GPa, and its tensile strength is 90 to 100 MPa. PEEK has a glass transition temperature of approximately 143°C (289°F) and a melting point of approximately 343°C (662°F). Some grades have useful working temperatures of up to 250°C (482°F). It is highly resistant to thermal degradation as well as to the invasion of organic and aqueous environments. It is susceptible to erosion by halogens, strong acids, some halogenated compounds and hydrocarbons under high-temperature conditions. It is completely soluble in concentrated sulfuric acid at room temperature.

Due to its ruggedness, PEEK is used in the manufacture of demanding applications such as bearings, piston components, pumps, HPLC chromatographic columns, compressor plate valves, and cable insulation layers. It is one of the few plastics compatible with ultra-high vacuum applications. It is widely used in aerospace, automotive, and chemical process industries.Polyether ether ketone is also used in nuclear environments, oil and geothermal wells, chemical industry, high-pressure valves, food processing equipment, high-vacuum equipment, etc.

The Effectiveness of Using PEEK in 3D Printing

PEKK is a member of the Polyaryletherketone (PAEK) family, but it is easier to print because it is a more amorphous material, limiting shrinkage to about 0.01%. However, processing conditions for producing PEEK or PEKK parts affect their crystallinity and hence their properties. Generally, materials with more crystallinity, such as polyetheretherketone, have better mechanical, chemical, and thermal properties than non-crystalline materials, such as PEKK printed by 3D. In fact, PEEK has been certified by NORSOK M-710 for its extremely high chemical resistance in the oil and gas industry. Unlike amorphous 3D-printed PEKK, which reaches a continuous use temperature (CUT) of 150°C even without post-processing, PEEK has a much higher CUT due to its crystallinity and can reach a CUT of 260°C.

Although printing with PEEK is generally considered difficult, it becomes easy if you have a Roboze Argo production system. With its heating chamber that ensures even heat flow and a HVP extruder that is responsible for depositing such viscous filaments, the Argo printer handles polyetheretherketone shrinkage excellently, ensuring a positioning accuracy of 10 μm. PEEK crystallinity achieved through the Argo printer is extremely high, ensuring optimal material quality in terms of mechanical, chemical, and thermal properties.