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PEKK · print state

PEKK-FFF

Properties of the FFF condition, compared with the other PEKK grades.

Pick when quoting as-printed extruded parts; expect strong anisotropy with Z-direction roughly 60–70 % of in-plane strength.

3D printingSpecialty cost $$$$$

What is PEKK-FFF?

PEKK-FFF is PEKK in the FFF condition — pick when quoting as-printed extruded parts; expect strong anisotropy with Z-direction roughly 60–70 % of in-plane strength. PEKK-FFF has a yield strength of 95 MPa (13.8 ksi) and a tensile strength of 93 MPa (13.5 ksi) — stronger than 93% of polymer grades. Elongation at break is 4% and the elastic modulus is 3.8 GPa (0.551 Msi). PEKK-FFF has a density of 1.3 g/cm³ (0.047 lb/in³), heavier than 69% of polymer grades. Its glass-transition temperature is 162°C (324 °F). Unfilled is the default condition FabDigit quotes; FFF is available on request or by drawing note.

Advantages

  • High strength — 95 MPa (13.8 ksi), better than 93% of polymer grades
  • High service temperature — 240°C (464 °F), better than 92% of polymer grades
  • Good corrosion resistance — 92/100, better than 91% of polymer grades
  • Stiff — 3.8 GPa (0.551 Msi), better than 84% of polymer grades
  • Tough — resists crack growth — 3.5 MPa·√m (3.19 ksi·√in), better than 80% of polymer grades

Limitations

  • High embodied carbon — 18 kg CO₂/kg, worse than 99% of polymer grades
  • Limited ductility — 4%, worse than 78% of polymer grades

PEKK-FFF properties

Typical room-temperature values for PEKK-FFF — 9 properties are specific to this condition; the rest are grade-level values shared by every PEKK grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.

Physical5

PEKK-FFF has a density of 1.3 g/cm³ (0.047 lb/in³), heavier than 69% of polymer grades. Its glass-transition temperature is 162°C (324 °F).

Density1.3 g/cm³0.05 lb/in³
Melting Temperature (Tm)332°C630 °F
Glass Transition (Tg)162°C324 °F
Water Absorption (24 h)0.15%
Water Absorption (Saturation)0.5%

Mechanical16

PEKK-FFF has a yield strength of 95 MPa (13.8 ksi) and a tensile strength of 93 MPa (13.5 ksi) — stronger than 93% of polymer grades. Elongation at break is 4% and the elastic modulus is 3.8 GPa (0.551 Msi).

Elastic (Young's) Modulus3.8 GPa0.55 Msi
Shear Modulus1.4 GPa0.2 Msi
Bulk Modulus7 GPa0.94 Msi
Poisson's Ratio0.4
Tensile Strength (Ultimate)93 MPa13.5 ksi
Yield Strength (0.2% offset)95 MPa13.8 ksi
Elongation at Break4%
Compressive Strength130 MPa18.9 ksi
Compressive Modulus3.5 GPa0.51 Msi
Flexural Strength148 MPa21.5 ksi
Flexural Modulus3.9 GPa0.57 Msi
Shear Strength65 MPa9.4 ksi
Fracture Toughness (K_IC)3.5 MPa·√m3.2 ksi·√in
Izod Impact, Notched41 J/m0.77 ft·lbf/in
Hardness, Shore D86 Shore D
Hardness, Rockwell M100 HRM

Thermal10

PEKK-FFF is rated for continuous service to 240°C (464 °F). It conducts heat at 0.26 W/m·K (0.15 BTU/hr·ft·°F), better than 76% of polymer grades. Thermal expansion is 48 µm/m·K (26.7 µin/in·°F).

Thermal Conductivity0.26 W/m·K0.15 BTU/hr·ft·°F
Specific Heat Capacity1,050 J/kg·K0.25 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)48 µm/m·K26.7 µin/in·°F
Max Service Temperature (continuous)240°C464 °F
Min Service Temperature-60°C-76 °F
Heat Deflection Temp. @ 0.45 MPa174°C345 °F
Heat Deflection Temp. @ 1.8 MPa160°C320 °F
Flammability (UL 94)V-0 at ≥1.5 mm
Limiting Oxygen Index40%
Max Service Temperature (short-term)300°C572 °F

Electrical7

PEKK-FFF is an electrical insulator with a dielectric strength of 22 kV/mm (558.8 V/mil) and a resistivity of 1×10¹⁴ Ω·m.

Electrical Resistivity1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
Dielectric Strength22 kV/mm559 V/mil
Dielectric Constant (1 MHz)3.3
Dissipation Factor (1 MHz)0.004
Volume Resistivity1×10¹⁶ Ω·cm
Surface Resistivity1×10¹⁵ Ω
Comparative Tracking Index (CTI)175 V

Chemical & Environmental3

Corrosion resistance is excellent (92/100), better than 91% of polymer grades. UV resistance is fair.

Corrosion ResistanceExcellent92/100
UV / Weathering ResistanceFair45/100
Chemical Resistance SummaryExcellent against fuels, hydraulic fluids (Skydrol), lubricants, steam, dilute acids/alkalis and most solvents; hydrolysis-resistant to ~250 °C. Attacked by concentrated sulfuric/nitric acid, some halogenated solvents cause swelling; UV exposure needs pigmented/protected grades.

Sustainability4

Producing a kilogram of PEKK-FFF takes about 330 MJ of energy and emits 18 kg of CO₂ — more than 99% of polymer grades. Typical recycled content is 0%.

Embodied Energy (primary production)330 MJ/kg141,875 BTU/lb
Embodied Carbon (primary production)18 kg CO₂/kg
Embodied Water500 L/kg59.9 gal/lb
Typical Recycled Content0%

Manufacturability7

PEKK-FFF's machinability is good (60/100, better than 51% of polymer grades); weldability good (55/100); formability fair (35/100).

MachinabilityGood60/100
WeldabilityGood55/100
Formability (cold)Fair35/100
PolishabilityGood60/100
Mold Shrinkage1.2%
Processing Melt Temperature (typ.)405°C761 °F
Mold Temperature (typ.)200°C392 °F

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Other PEKK grades and fills

PEKK is also supplied in 9 other conditions. The full side-by-side table is on the PEKK overview.

Working with PEKK-FFF

Is PEKK easy to machine?

Machines like PEEK with sharp carbide/PCD tools, high speed, light feeds and air or flood cooling; stress-relieve (annealing near 200 °C) before finish cuts to avoid distortion.

Can PEKK be welded?

Joinable by laser, ultrasonic, IR and hot-plate welding as well as PAEK-compatible epoxy adhesives after plasma or abrasive surface activation; no solvent bonding.

Can PEKK be formed, bent or molded?

Requires 340–420 °C melt, 160–230 °C tools and dry feedstock (<0.02 % moisture, 150 °C for 3–4 h); FFF needs a 400 °C-class hot end plus 130–200 °C chamber and post-print anneal for crystallinity and Z-strength.

What surface finishes work on PEKK?

Sand/bead-blast or vapour-smooth-free finishing only; no anodizing — parts can be painted or metallised after plasma treatment, and machined surfaces polish to a semi-gloss tan finish.

PEKK chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
carbon fiberCF variants only0 – 300
glass fiberGF variants only0 – 400
carbon nanotubeESD variant only0 – 50
polyetherketoneketone repeat unit (from T/I isomer ratio ~60:40 to 80:20 sets Tm; unfilled defaultbalance

PEKK-FFF — frequently asked

What is PEKK-FFF used for?

PEKK-FFF is typically used for aerospace brackets, air and fluid ducting, satellite components, aerospace composite tooling and structures, electrical insulation parts and implantable orthopaedic devices. In short: space-grade performance.

What is the yield strength of PEKK-FFF?

PEKK-FFF has a typical yield strength of 95 MPa (13.8 ksi) and a tensile strength of 93 MPa (13.5 ksi) — stronger than 93% of polymer grades. Strength varies by condition: see the 10 listed tempers.

Is PEKK-FFF easy to machine?

Reasonably — machinability is rated good (60/100, better than 51% of polymer grades). Machines like PEEK with sharp carbide/PCD tools, high speed, light feeds and air or flood cooling; stress-relieve (annealing near 200 °C) before finish cuts to avoid distortion.

Can PEKK-FFF be welded?

Yes — weldability is rated good (55/100). Joinable by laser, ultrasonic, IR and hot-plate welding as well as PAEK-compatible epoxy adhesives after plasma or abrasive surface activation; no solvent bonding.

What surface finishes work on PEKK-FFF?

Sand/bead-blast or vapour-smooth-free finishing only; no anodizing — parts can be painted or metallised after plasma treatment, and machined surfaces polish to a semi-gloss tan finish.

Can PEKK-FFF be formed, bent or molded?

Requires 340–420 °C melt, 160–230 °C tools and dry feedstock (<0.02 % moisture, 150 °C for 3–4 h); FFF needs a 400 °C-class hot end plus 130–200 °C chamber and post-print anneal for crystallinity and Z-strength.

What is the maximum service temperature of PEKK-FFF?

PEKK-FFF is rated for continuous use to about 240°C (464 °F), and briefly to 300°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Can FabDigit make parts in PEKK-FFF?

Yes — PEKK-FFF is available for 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.

Sources

  1. Kepstan PEKK 6000/7000/8000 series technical data and processing guideArkema (2022)
  2. Antero 800NA and Antero 840CN03 PEKK FDM material datasheetsStratasys (2023)
  3. Engineering Plastics — polyaryletherketone property overviewASM International (2000)
  4. CAMPUS / UL Prospector PAEK property listingsCWFG / UL Solutions (2024)
  5. ISO 10993 series (biological evaluation of medical devices)ISO (2018)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.