3D Printing Info

Filament comparison

PA6/66 vs PEEK-CF

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

PA66 (Nylon 66) guideFibre-reinforced PEEK guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA6/66 comparisonsMore PEEK-CF comparisons
PA6/66 vs PEEK-CF — documented properties and sources
PropertyPA66 (Nylon 66)PAFibre-reinforced PEEKHIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshotsNot documented$597.50/kg median; $448.00–$695.00/kg across 5 dated product listings
Identity & Market
Base polymer / chemistryPolyamide 66, condensed from hexamethylenediamine and adipic acid; melts around 40 °C above PA6[1]Short-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[2][3][4][5]
Densityg/cm³1.14 (extruded unfilled PA66 stock)[6]1.39 (ISO 1183)[2]
Typical priceUSD/kgNot documented1 kg-equivalent spools span 448–972; the middle of the market is about 598[3][4][7]
Price range across brandsUSD/kgNot documented448-972 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[3][4][7][8]
Market availability1–5Special order, 1–2 makers worldwide — no unfilled PA66 filament appeared in any catalogue searched, and the 3DXTech nylon range offers PA6, PA12 and a 6/66 copolymer but no straight PA66[3][9]Niche, a handful of specialist brands[3][4]
Spool sizes & diametersNot documented1.75 and 2.85 mm; 200 g to 2 kg spools[3][4]
Typical applicationsNot documentedStiff aerospace and oil-and-gas parts where PEEK alone is not rigid enough[2]
Printing Parameters
Enclosure / chamber requirement1–5Enclosure required (passive)[1]Actively heated chamber required[10][11]
Warping tendency1–5Not documentedModerate — needs adhesion aid or draught shield; the fibre cuts PEEK's crystallisation shrinkage[2]
Overall printing difficulty1–5Advanced — enclosure, hardware upgrades, tuning[1]Expert / industrial hardware only[10][11]
Hardware Wear & Reliability
Nozzle hardness required1–4Not documentedHardened steel required[2]
Abrasiveness1–5Not documentedHighly abrasive — standard CF composite[2]
Nozzle clog risk1–5Very high — frequent jams without careful setup[12][13]High — 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[14][15]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Very high (>2 %)[13]Not documented
Equilibrium moisture content at ~50 % RH%8.5 at saturation on extruded PA66 stock (ASTM D570) — the highest uptake of any polymer in this dataset[6]0.06 in 24 h on extruded CF30 stock (ASTM D570)[5]
Effect of moisture on strengthMeasured dry against wet on printed specimens at 6.16 % moisture (Polymaker CoPA): tensile 78.0 → 34.3 MPa, Young's modulus 2703 → 724 MPa, flexural strength 109.8 → 22.6 MPa, while notched Charpy rises 6.9 → 27.7 kJ/m² and elongation 12.7 → 13.2 %[16][12]No 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[14]
Mechanical Properties
Tensile strength (XY)MPa82.7 at yield and 84.8 at break on extruded PA66 stock (ASTM D638; converted from 12,000 and 12,300 psi) — no printed figure exists because no unfilled PA66 filament was found[6]105 at break (printed XY, ISO 527, CF10); 121 at yield on extruded CF30 stock (ASTM D638)[2][5]
Young's modulusMPa2413 on extruded PA66 stock (ASTM D638; converted from 350,000 psi)[6]8100 (printed XY, ISO 527, CF10) — more than double unfilled PEEK; 6343 on extruded CF30 stock (ASTM D638)[2][5]
Elongation at break%50 at break on extruded PA66 stock (ASTM D638)[6]3 at break (printed XY, ISO 527), against 28 for unfilled PEEK[2][17]
Flexural strengthMPa113.8 on extruded PA66 stock (ASTM D790; converted from 16,500 psi)[6]136 (printed XY, ISO 178, CF10); 193 on extruded CF30 stock (ASTM D790)[2][5]
Flexural modulusMPa3034 on extruded PA66 stock (ASTM D790; converted from 440,000 psi)[6]8300 (printed XY, ISO 178, CF10); 7171 on extruded CF30 stock (ASTM D790)[2][5]
Other impact dataIzod 53 J/m on extruded PA66 stock, converted from 1.0 ft-lb/in (ASTM D256)[6]Izod notched 61.9 J/m on extruded CF30 stock, converted from 1.16 ft-lb/in (ASTM D256)[5]
Brittleness1–5Not documentedBrittle — snaps with little warning; elongation falls from 28 % to 3 %[2][17]
Hardness (scale-specific)Shore A / Shore D / RockwellShore D 86 and Rockwell 85 (108) — the source does not name the scales on extruded PA66 stock (ASTM D2240, D785)[6]Rockwell M107 on extruded PEEK-CF30 stock (ASTM D785), against M100 unfilled[5][18]
Creep resistance / sustained load1–5Not documentedExcellent — holds load for years. Ensinger rates carbon-fibre PEEK stock as very highly creep resistant and specifies 260 °C continuous service[5]
Fatigue / repeated-flex resistance1–5Excellent — living hinges viable[1]Good. 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[19][2][17]
Elasticity / flexibility1–5Semi-flexible[12]Rigid[2]
Wear resistance & frictionWear factor 200e-10 in3*min/(ft*lb*h) on extruded PA66 stock (ASTM D3702); Ensinger lists very good slide and wear properties[6]Not documented
Thermal Properties
HDT at 0.45 MPa°C232 on extruded PA66 stock (ASTM D648 at 66 psi; converted from 450 °F)[6]265 (printed XY, ISO 75 at 0.45 MPa, CarbonX PEEK+CF10) against 140 for unfilled PEEK[2][17]
HDT at 1.8 MPa°C90 on extruded PA66 stock (ASTM D648 at 264 psi; converted from 194 °F) — the gap to the 0.45 MPa figure is the widest in the dataset[6]316 on extruded CF30 stock, converted from 600 °F at 264 psi (ASTM D648)[5]
Glass transition (Tg)°CNot documented143 (DSC, CarbonX PEEK+CF10) — the fibre does not move the glass transition[2]
Melting point / Vicat°C255 melting on extruded PA66 stock (ASTM D2133; converted from 491 °F)[6]334 melting on extruded CF30 stock, converted from 633 °F[5]
Continuous service temperature°C85 long term and 149 short term on extruded PA66 stock (converted from 185 °F and 300 °F)[6]260 long-term on extruded CF30 stock, converted from 500 °F; 300 short term[5]
Thermal expansion (CTE)µm/m·K81.0 (extruded PA66 stock, ASTM D696; source states 4.5e-5 in/in/°F)[6]14.4 (extruded PEEK-CF30 stock, ASTM D696; source states 0.80e-5 in/in/°F) — about a third of unfilled PEEK[5][18]
Flammability / UL 94UL 94 V-2 on extruded PA66 stock[6]UL 94 V-0 on the base resin; Ensinger lists extruded PEEK-CF30 stock as inherently flame resistant[17][5]
Environment & Chemical
Electrical & ESD propertiesVolume resistance 1e15 ohm-cm and dielectric constant 4 on extruded PA66 stock (ASTM D257, D150)[6]Surface resistance above 10⁹ ohm/sq — not static-dissipative (ASTM D257)[2]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[20]Moderate — 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[20]
VOC emission rateµg/minUp to 180 caprolactam, the dominant VOC from nylon; total VOC reached nearly 200 µg/min, the highest of the nine filaments tested[20]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median — low for ultrafine particles despite the highest VOC mass of any filament tested[20]Not documented
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament — the largest single-VOC emission rate measured in the study[20]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[20]Ventilated room or enclosure recommended[20]
Dust & fibre handling hazardNot documentedCarbon fibre is bound in the matrix; sanding dust should not be inhaled[2]
Solvents & Solubility
Soluble inDissolved at 23 °C by formic acid above ~80 %, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — laboratory reagents.[21]95–98 wt% sulphuric acid dissolves the matrix at 40–70 °C and leaves the fibre. Nothing else touches PEEK.[22][23]
Softened or crazed byZinc chloride solutions stress-crack it — 10 % marginal, 37 % not resistant; alcoholic calcium chloride dissolves it.[21]Concentrated nitric, hydrofluoric, hydrobromic and hydriodic acids attack it; DCM, DMSO and THF swell thin-walled sections.[24][23]
Solvent welding & smoothing agentNone — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[21]None — no solvent softens PEEK, so parts are joined thermally or mechanically, never chemically.[24][23]

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. PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
  2. CarbonX Carbon Fiber PEEK Technical Data Sheet v3 3DXTech · 2026-08 · tds
  3. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  4. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  5. TECAPEEK CF30 black (PEEK-CF30) — stock shape properties Ensinger · 2026-08 · tds
  6. TECAMID 66 natural (PA66) — stock shape properties Ensinger · 2026-08 · tds
  7. IEMAI 3D CF-PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  8. IEMAI 3D GF-PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  9. Polymaker product catalogue Polymaker · 2026-08 · vendor
  10. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  11. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  12. Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
  13. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  14. CARBONX PEEK+CF10 — product page (print recommendations) 3DXTech · 2026-08 · doc
  15. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  16. PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
  17. ThermaX PEEK Technical Data Sheet v3 3DXTech · 2026-08 · tds
  18. TECAPEEK natural (PEEK) — stock shape properties Ensinger · 2026-08 · tds
  19. PEEK polymers — product overview Victrex · 2026-08 · doc
  20. 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
  21. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  22. 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
  23. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  24. What solvents are not compatible with PEEK? — fluidics technical FAQ IDEX Health & Science · 2026-08 · doc