3D Printing Info

Filament comparison

PEEK-CF vs PET-CF

Compare printing settings, strength, heat resistance, dated prices and sources.

Fibre-reinforced PEEK guideCarbon-fibre PET (PET-CF) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PEEK-CF comparisonsMore PET-CF comparisons
PEEK-CF vs PET-CF — documented properties and sources
PropertyFibre-reinforced PEEKHIGHTEMPCarbon-fibre PET (PET-CF)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$597.50/kg median; $448.00–$695.00/kg across 5 dated product listings$39.99/kg median; $26.00–$49.98/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryShort-fibre reinforced PEEK. 3DXTech's CarbonX grade is nominally 10 wt% carbon and its FibreX grade 20 wt% glass; LEHVOSS Luvocom 3F PEEK CF 9676 is 15 wt% carbon; Ensinger's machining stock runs to 30 wt% carbon[1][2][3][4]Semi-crystalline PET reinforced with carbon fibre — a different polymer from PETG-CF, with the glycol modifier removed so the matrix can crystallise[5][6]
Densityg/cm³1.39 (ISO 1183)[1]1.29 (Bambu Lab) and 1.34 (Fiberon PET-CF17), ISO 1183[5][6]
Typical priceUSD/kg1 kg-equivalent spools span 448–972; the middle of the market is about 598[2][3][7]1 kg spools cluster near 45[5][8]
Price range across brandsUSD/kg448-972 across formats and filler types; IEMAI 3D CF-PEEK and GF-PEEK 448 at 1 kg, 3DXTech CarbonX PEEK+CF10 598 at 2 kg and FibreX PEEK+GF20 695 at 1 kg, Luvocom 3F PEEK CF 9676 648 at 2 kg[2][3][7][9]26–50 across brands; ELEGOO 26 in a 5 kg pack, Bambu Lab 45, Fiberon 50[10][5][8]
Market availability1–5Niche, a handful of specialist brands[2][3]Available from several mainstream brands[5][8][10]
Spool sizes & diameters1.75 and 2.85 mm; 200 g to 2 kg spools[2][3]1.75 mm; 0.5 and 1 kg spools[8][5]
Typical applicationsStiff aerospace and oil-and-gas parts where PEEK alone is not rigid enough[1]Load-bearing parts that must survive above PETG's 70 °C ceiling without moving to PA or PC[5][6]
Printing Parameters
Nozzle temperature°CNot documented260–290 (Bambu Lab)[5]
Bed temperature°CNot documented80–100 (Bambu Lab)[5]
Enclosure / chamber requirement1–5Actively heated chamber required[11][12]Enclosure recommended — Bambu Lab specifies a 45–60 °C chamber[5]
Recommended chamber temperature°CNot documented45–60 (Bambu Lab)[5]
Part cooling fanNot documented0–60 % (Bambu Lab)[5]
Bed surface & adhesion aidNot documentedTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[13][14]
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented8 at Bambu Lab's 100 mm/s cap on a 0.4 mm nozzle at 0.2 mm layer — half the speed it allows for PETG-CF[5][15]
Warping tendency1–5Moderate — needs adhesion aid or draught shield; the fibre cuts PEEK's crystallisation shrinkage[1]Not documented
Bed-adhesion difficulty1–5Not documentedNeeds the right surface or a thin adhesive — the problem is releasing the part, not sticking it[13][14]
Stringing / oozing tendency1–5Not documentedModerate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[14]
Overall printing difficulty1–5Expert / industrial hardware only[11][12]Advanced — enclosure, hardware upgrades, tuning[5]
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required[1]Hardened steel required[5]
Abrasiveness1–5Highly abrasive — standard CF composite[1]Highly abrasive — standard CF composite[5]
Nozzle clog risk1–5High — jams from moisture, heat creep or particles; 3DXTech adds a hardened 0.4 mm minimum nozzle and 0.25 mm layers to the mandatory 120 °C pre-dry[16][17]Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for carbon-filled composites[17]
Heat-creep / jam sensitivity1–5Not documentedSlightly sensitive[18]
Hotend requirementNot documentedNo special hot-end required[18]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Not documentedModerate — 0.37 % saturated at 25 °C / 55 % RH (Bambu Lab); 0.53 % equilibrium (Fiberon)[5][6]
Equilibrium moisture content at ~50 % RH%0.06 in 24 h on extruded CF30 stock (ASTM D570)[4]0.37 saturated at 25 °C / 55 % RH (Bambu Lab); 0.53 equilibrium (Fiberon PET-CF17)[5][6]
Drying temperature & timeNot documented80 °C for 8–12 h (Bambu Lab) — the longest and hottest dry in the polyester family; Fiberon specifies 100 °C for 10 h[5][6]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[19]
Effect of moisture on strengthNo dry-versus-conditioned figures are published; 3DXTech mandates a 120 °C, 4 h pre-dry before every print because trapped water flashes to steam at these nozzle temperatures[16]Bambu Lab publishes its whole mechanical table under the heading "Mechanical Properties (Dry state)" — the quoted figures apply only to dried filament[5]
Storage requirementNot documentedSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[19][14]
Hydrolysis at melt temperatureNot documentedThe 80–100 °C dry both suppliers mandate is far above the 55–65 °C used for PETG, consistent with a melt-hydrolysis risk in the semi-crystalline PET matrix; neither publishes a molecular-weight loss figure[5][6]
Mechanical Properties
Tensile strength (XY)MPa105 at break (printed XY, ISO 527, CF10); 121 at yield on extruded CF30 stock (ASTM D638)[1][4]65.9 (Fiberon) to 74 (Bambu Lab) printed XY, ISO 527[5][6]
Young's modulusMPa8100 (printed XY, ISO 527, CF10) — more than double unfilled PEEK; 6343 on extruded CF30 stock (ASTM D638)[1][4]4730 ± 260 (Bambu Lab) and 5481 ± 224 (Fiberon) printed XY, ISO 527[5][6]
Elongation at break%3 at break (printed XY, ISO 527), against 28 for unfilled PEEK[1][20]2.4 ± 0.5 printed XY, ISO 527 (Fiberon PET-CF17)[6]
Flexural strengthMPa136 (printed XY, ISO 178, CF10); 193 on extruded CF30 stock (ASTM D790)[1][4]109.3 ± 2.0 printed XY, ISO 178 (Fiberon PET-CF17)[6]
Flexural modulusMPa8300 (printed XY, ISO 178, CF10); 7171 on extruded CF30 stock (ASTM D790)[1][4]4744 ± 136 printed XY, ISO 178 (Fiberon PET-CF17)[6]
Charpy impact, notchedkJ/m²Not documented5.1 ± 0.2 printed XY, ISO 179 notched (Fiberon PET-CF17); unnotched 25.1 ± 2.8[6]
Other impact dataIzod notched 61.9 J/m on extruded CF30 stock, converted from 1.16 ft-lb/in (ASTM D256)[4]Not documented
Layer adhesion / Z tensileMPaNot documented27.9 (Fiberon) and 35 ± 5 (Bambu Lab) printed Z, ISO 527[5][6]
Brittleness1–5Brittle — snaps with little warning; elongation falls from 28 % to 3 %[1][20]Very brittle — elongation at break 2.4 % in XY and 0.8 % in Z[6]
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell M107 on extruded PEEK-CF30 stock (ASTM D785), against M100 unfilled[4][21]Not documented
Creep resistance / sustained load1–5Excellent — holds load for years. Ensinger rates carbon-fibre PEEK stock as very highly creep resistant and specifies 260 °C continuous service[4]Good — no creep test found; annealed PET-CF holds a 105 °C HDT at 1.8 MPa and a 4730–5481 MPa modulus against 1500–2311 for PETG[6][5]
Fatigue / repeated-flex resistance1–5Good. Victrex rates PEEK for long-term fatigue as well as creep; the fibre cuts elongation at break from 28 % to 3 %, which limits repeated large-strain flexing[22][1][20]Below average — no S-N curve; elongation at break is 2.4 % in XY and 0.8 % in Z, against 5.2–9.3 % for unfilled PETG[6]
Elasticity / flexibility1–5Rigid[1]Rigid[5]
Z strength as % of XY%Not documented42 (Fiberon) to 47 (Bambu Lab), printed[5][6]
Thermal Properties
HDT at 0.45 MPa°C265 (printed XY, ISO 75 at 0.45 MPa, CarbonX PEEK+CF10) against 140 for unfilled PEEK[1][20]147.5 (Fiberon) and 205 (Bambu Lab), ISO 75 at 0.45 MPa[5][6]
HDT at 1.8 MPa°C316 on extruded CF30 stock, converted from 600 °F at 264 psi (ASTM D648)[4]105 (Fiberon) and 182 (Bambu Lab), ISO 75 at 1.8 MPa[5][6]
Glass transition (Tg)°C143 (DSC, CarbonX PEEK+CF10) — the fibre does not move the glass transition[1]75 (Bambu Lab) and 79.3 (Fiberon), DSC[5][6]
Melting point / Vicat°C334 melting on extruded CF30 stock, converted from 633 °F[4]241.3 (Fiberon) and 250 (Bambu Lab) melting, DSC; Vicat 226–238[5][6]
Continuous service temperature°C260 long-term on extruded CF30 stock, converted from 500 °F; 300 short term[4]Not documented
Annealing responseNot documentedThe PET matrix crystallises on annealing, which is what separates this grade from PETG-CF[6][5]
Thermal expansion (CTE)µm/m·K14.4 (extruded PEEK-CF30 stock, ASTM D696; source states 0.80e-5 in/in/°F) — about a third of unfilled PEEK[4][21]Not documented
Flammability / UL 94UL 94 V-0 on the base resin; Ensinger lists extruded PEEK-CF30 stock as inherently flame resistant[20][4]Flammable; no UL 94 rating published for standard grades[23]
Environment & Chemical
Chemical resistanceNot documentedWithstands acids, alkalis, oils and UV exposure[14]
Food contactNot documentedNot certified for food contact as filament[14]
Biodegradability / compostabilityNot documentedNot biodegradable[14]
RecyclabilityNot documentedNot accepted in household plastic collection[14]
Electrical & ESD propertiesSurface resistance above 10⁹ ohm/sq — not static-dissipative (ASTM D257)[1]Surface resistivity above 10¹² ohm — insulating (Fiberon PET-CF17, ANSI/ESD S11.11)[6]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised. None of these polymers was in the chamber study, and all are processed far above the temperatures it covered[24]Moderate — measurable VOCs and UFPs, ventilation advised[24]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[24]Ventilated room or enclosure recommended[24][5]
Dust & fibre handling hazardCarbon fibre is bound in the matrix; sanding dust should not be inhaled[1]Carbon fibre is bound in the matrix; sanding dust should not be inhaled[6]
Post-Processing
Sanding & machiningNot documentedSands poorly — the material is tough and gums rather than powders[18]
Gluing & solvent weldingNot documentedCyanoacrylate; no common solvent welds PETG cleanly[18]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[18]
Support material pairingNot documentedPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[18]
Dimensional accuracy & detailNot documentedBambu Lab markets it on low warping and shrinkage relative to other high-temperature composites[5]
Solvents & Solubility
Soluble in95–98 wt% sulphuric acid dissolves the matrix at 40–70 °C and leaves the fibre. Nothing else touches PEEK.[25][26]None common; fluorinated solvents such as hexafluoroisopropanol dissolve linear polyester at 23 °C. Laboratory only.[27][26]
Softened or crazed byConcentrated nitric, hydrofluoric, hydrobromic and hydriodic acids attack it; DCM, DMSO and THF swell thin-walled sections.[28][26]Ensinger rates polyester not resistant to chloroform or dichloromethane and only conditionally resistant to acetone and MEK.[26]
Solvent welding & smoothing agentNone — no solvent softens PEEK, so parts are joined thermally or mechanically, never chemically.[28][26]Dichloromethane attacks polyester and can be brushed on, but the carbon fibre blocks any useful surface flow.[26][29]

Material entries describe families or representative grades, not an interchangeable specification for every spool. Test methods, orientations and conditions may differ. Unknown values are marked “Not documented”. Prices and source dates remain historical snapshots; check the linked guide for product details. Differences highlight text, not a universal winner.

Sources for this comparison

  1. CarbonX Carbon Fiber PEEK Technical Data Sheet v3 3DXTech · 2026-08 · tds
  2. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  3. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  4. TECAPEEK CF30 black (PEEK-CF30) — stock shape properties Ensinger · 2026-08 · tds
  5. Bambu Filament Technical Data Sheet — PET-CF Bambu Lab · 2026-08 · tds
  6. Fiberon PET-CF17 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  7. IEMAI 3D CF-PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  8. Polymaker product catalogue Polymaker · 2026-08 · vendor
  9. IEMAI 3D GF-PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  10. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  11. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  12. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  13. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  14. PETG — material basics Polymaker Wiki · 2026-08 · doc
  15. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  16. CARBONX PEEK+CF10 — product page (print recommendations) 3DXTech · 2026-08 · doc
  17. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  18. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  19. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  20. ThermaX PEEK Technical Data Sheet v3 3DXTech · 2026-08 · tds
  21. TECAPEEK natural (PEEK) — stock shape properties Ensinger · 2026-08 · tds
  22. PEEK polymers — product overview Victrex · 2026-08 · doc
  23. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  24. Emissions of Ultrafine Particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments (Azimi et al.) Environmental Science & Technology 50(3) 1260-1268 · 2016-01 · paper
  25. The Effects of Sulfonated Poly(ether ether ketone) Ion Exchange Preparation Conditions on Membrane Properties Yee, Zhang & Ladewig, Membranes 3(3) 182–195 · 2013-07 · paper
  26. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  27. Resistance of Ultramid, Ultraform and Ultradur to chemicals (TI-KTU/AS-28 e) BASF · 2000-10 · tds
  28. What solvents are not compatible with PEEK? — fluidics technical FAQ IDEX Health & Science · 2026-08 · doc
  29. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc