3D Printing Info

Filament comparison

PEEK-CF vs rPETG

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

Fibre-reinforced PEEK guideRecycled PETG (rPETG) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PEEK-CF comparisonsMore rPETG comparisons
PEEK-CF vs rPETG — documented properties and sources
PropertyFibre-reinforced PEEKHIGHTEMPRecycled PETG (rPETG)PETG
Market snapshot
Listing priceUSD/kg; dated snapshots$597.50/kg median; $448.00–$695.00/kg across 5 dated product listings$28.99/kg median; $17.24–$39.98/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]PETG regranulated from recycled polyester waste; Polymaker's Fiberon PETG-rCF08 adds 8 wt% recycled carbon fibre[5][6][7]
Densityg/cm³1.39 (ISO 1183)[1]1.27 (Prusament) and 1.30 (Fiberon PETG-rCF08), ISO 1183[5][7]
Typical priceUSD/kg1 kg-equivalent spools span 448–972; the middle of the market is about 598[2][3][8]1 kg spools cluster near 29[2][9][10][11]
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][8][12]17–40 across brands; Filament PM RePETG 17, 3DXTech ECOMAX 26, GreenGate3D 32, Fiberon rCF08 40[2][9][10][11]
Market availability1–5Niche, a handful of specialist brands[2][3]Available from several mainstream brands[2][9][10]
Spool sizes & diameters1.75 and 2.85 mm; 200 g to 2 kg spools[2][3]1.75 and 2.85 mm; 0.5, 1 and 3 kg spools[10][9]
Typical applicationsStiff aerospace and oil-and-gas parts where PEEK alone is not rigid enough[1]Not documented
Diameter tolerance± mmNot documented±0.05 (Prusament PETG Recycled), against ±0.02 for virgin Prusament PETG[5][13]
Printing Parameters
Nozzle temperature°CNot documented250 ± 10 (Prusament); 230–255 (Spectrum)[5][6]
Bed temperature°CNot documented80 ± 10 (Prusament); 60–80 (Spectrum)[5][6]
Enclosure / chamber requirement1–5Actively heated chamber required[14][15]Open frame is fine — Spectrum states a closed chamber is not necessary[6]
Part cooling fanNot documented50 % (Prusament); up to 100 % (Spectrum)[5][6]
Bed surface & adhesion aidNot documentedTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[13][16]
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][16]
Stringing / oozing tendency1–5Not documentedModerate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[16]
Overall printing difficulty1–5Expert / industrial hardware only[14][15]Easy — minor profile tuning; Spectrum describes printing as similar to standard PETG[6]
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required[1]Brass fine indefinitely[5]
Abrasiveness1–5Highly abrasive — standard CF composite[1]Not documented
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[17][18]Low — recycled PETG prints on the same hardware as virgin PETG: no special hot-end, no drybox and no hardened nozzle[19][20]
Heat-creep / jam sensitivity1–5Not documentedSlightly sensitive[19]
Hotend requirementNot documentedNo special hot-end required[19]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Not documentedModerate (0.3–0.8 %) — recycled PETG shares the virgin matrix, which reaches 0.40 % saturated at 25 °C / 55 % RH[13]
Equilibrium moisture content at ~50 % RH%0.06 in 24 h on extruded CF30 stock (ASTM D570)[4]0.07 after 24 h and 0.10 after 7 days at 24 °C / 22 % RH (Prusa Polymers)[5]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[21]
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[17]Polymaker groups PETG with nylon, PVA and TPU as highly hygroscopic; no dry-versus-conditioned strength figures are published for this grade and the loss shows as bubbling and poor layer adhesion[21]
Storage requirementNot documentedSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[21][16]
Mechanical Properties
Tensile strength (XY)MPa105 at break (printed XY, ISO 527, CF10); 121 at yield on extruded CF30 stock (ASTM D638)[1][4]43 ± 1.8 printed horizontal at yield, ISO 527-1 (Prusament), against 47 ± 2 for virgin Prusament PETG; Spectrum quotes 52 at yield on moulded specimens[5][13][6]
Young's modulusMPa8100 (printed XY, ISO 527, CF10) — more than double unfilled PEEK; 6343 on extruded CF30 stock (ASTM D638)[1][4]1500 printed horizontal, 1600 printed vertical (Prusament, ISO 527-1) — the same as virgin Prusament PETG[5][13]
Elongation at break%3 at break (printed XY, ISO 527), against 28 for unfilled PEEK[1][22]4.5 at yield printed (Prusament); Spectrum quotes 400 at break on moulded specimens[5][6]
Flexural strengthMPa136 (printed XY, ISO 178, CF10); 193 on extruded CF30 stock (ASTM D790)[1][4]63 ± 1 printed horizontal, ISO 178 (Prusament), against 66 ± 2 for virgin Prusament PETG[5][13]
Flexural modulusMPa8300 (printed XY, ISO 178, CF10); 7171 on extruded CF30 stock (ASTM D790)[1][4]1800 printed horizontal, ISO 178 (Prusament)[5]
Charpy impact, notchedkJ/m²Not documented12 ± 1 printed horizontal and 15 ± 3 printed vertical, ISO 179-1 notched (Prusament)[5]
Other impact dataIzod notched 61.9 J/m on extruded CF30 stock, converted from 1.16 ft-lb/in (ASTM D256)[4]Charpy unnotched 25 ± 3 printed horizontal and 38 ± 11 printed vertical (Prusament, ISO 179-1)[5]
Layer adhesion / Z tensileMPaNot documented15 ± 5 (Prusa Polymers interlayer adhesion test), against 18 ± 4 for virgin Prusament PETG[5][13]
Brittleness1–5Brittle — snaps with little warning; elongation falls from 28 % to 3 %[1][22]Moderate[5]
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell M107 on extruded PEEK-CF30 stock (ASTM D785), against M100 unfilled[4][23]74 Shore D (Prusa Polymers method) — the same as virgin Prusament PETG[5][13]
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]Below average — no recycled-grade creep test; virgin PETG sagged from 12 to 17.1–20.4 mm over 5 days at 1.25 kg[24][25][26][27]
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[28][1][22]Moderate — no recycled-grade S-N curve; virgin printed PETG ran 79 000–193 000 cycles at 30 % of tensile strength[29]
Elasticity / flexibility1–5Rigid[1]Slightly flexible in thin sections[5]
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][22]68 (ISO 75, 0.45 MPa) — the same as virgin Prusament PETG; Spectrum quotes 70[5][13][6]
HDT at 1.8 MPa°C316 on extruded CF30 stock, converted from 600 °F at 264 psi (ASTM D648)[4]68 (ISO 75, 1.8 MPa)[5]
Glass transition (Tg)°C143 (DSC, CarbonX PEEK+CF10) — the fibre does not move the glass transition[1]Not documented
Melting point / Vicat°C334 melting on extruded CF30 stock, converted from 633 °F[4]Not documented
Continuous service temperature°C260 long-term on extruded CF30 stock, converted from 500 °F; 300 short term[4]Not documented
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][23]Not documented
Flammability / UL 94UL 94 V-0 on the base resin; Ensinger lists extruded PEEK-CF30 stock as inherently flame resistant[22][4]Flammable; no UL 94 rating published for standard grades[30]
Environment & Chemical
Chemical resistanceNot documentedWithstands acids, alkalis, oils and UV exposure[16]
Food contactNot documentedNot certified for food contact as filament[16]
Biodegradability / compostabilityNot documentedNot biodegradable[16]
RecyclabilityNot documentedThe feedstock itself — Spectrum describes collecting, shredding and re-homogenising PETG waste[6]
Electrical & ESD propertiesSurface resistance above 10⁹ ohm/sq — not static-dissipative (ASTM D257)[1]Not documented
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[31]Moderate — measurable VOCs and UFPs, ventilation advised[31]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[31]Open a window / occasional ventilation[31]
Dust & fibre handling hazardCarbon fibre is bound in the matrix; sanding dust should not be inhaled[1]Not documented
Post-Processing
Sanding & machiningNot documentedSands poorly — the material is tough and gums rather than powders[19]
Gluing & solvent weldingNot documentedCyanoacrylate; no common solvent welds PETG cleanly[19]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[19]
Support material pairingNot documentedPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[19]
Solvents & Solubility
Soluble in95–98 wt% sulphuric acid dissolves the matrix at 40–70 °C and leaves the fibre. Nothing else touches PEEK.[32][33]No common workshop solvent; 1,2-dichloroethane destroys it inside a week and dichloromethane — a carcinogen — dissolves the surface.[34][35]
Softened or crazed byConcentrated nitric, hydrofluoric, hydrobromic and hydriodic acids attack it; DCM, DMSO and THF swell thin-walled sections.[36][33]Acetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[34]
Solvent welding & smoothing agentNone — no solvent softens PEEK, so parts are joined thermally or mechanically, never chemically.[36][33]Dichloromethane brushed on is the only agent that smooths PETG — a controlled carcinogen, not workshop stock.[35]

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. Prusament PETG Recycled Technical Datasheet Prusa Polymers · 2026-08 · tds
  6. Spectrum r-PETG Technical Data Sheet Spectrum Filaments · 2026-08 · tds
  7. Fiberon PETG-rCF08 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  8. IEMAI 3D CF-PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  9. GreenGate3D Recycled PET-G — product data GreenGate3D · 2026-08 · vendor
  10. Polymaker product catalogue Polymaker · 2026-08 · vendor
  11. Filament PM RePETG technical data sheet Filament PM (Plasty Mladec) · 2026-08 · tds
  12. IEMAI 3D GF-PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  13. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  14. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  15. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  16. PETG — material basics Polymaker Wiki · 2026-08 · doc
  17. CARBONX PEEK+CF10 — product page (print recommendations) 3DXTech · 2026-08 · doc
  18. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  19. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  20. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  21. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  22. ThermaX PEEK Technical Data Sheet v3 3DXTech · 2026-08 · tds
  23. TECAPEEK natural (PEEK) — stock shape properties Ensinger · 2026-08 · tds
  24. PCTG vs PETG comparison — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  25. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  26. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  27. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  28. PEEK polymers — product overview Victrex · 2026-08 · doc
  29. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  30. Prusament PETG V0 Technical Datasheet Prusa Polymers · 2026-08 · tds
  31. 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
  32. 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
  33. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  34. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  35. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  36. What solvents are not compatible with PEEK? — fluidics technical FAQ IDEX Health & Science · 2026-08 · doc