3D Printing Info

Filament comparison

PA6-CF vs PEI 9085

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

Carbon-fibre PA6 (PA6-CF) guidePEI (ULTEM 9085) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PA6-CF comparisonsMore PEI 9085 comparisons
PA6-CF vs PEI 9085 — documented properties and sources
PropertyCarbon-fibre PA6 (PA6-CF)PAPEI (ULTEM 9085)HIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$62.48/kg median; $39.00–$133.32/kg across 6 dated product listings$309.80/kg median; $220.00–$392.00/kg across 6 dated product listings
Identity & Market
Base polymer / chemistryPA6 reinforced with chopped carbon fibre — Polymaker's grade is 20 wt%[1][2]Polyetherimide, ULTEM 9085 grade — the flame-retardant PEI used for aircraft interiors[3]
Densityg/cm³1.09 (Bambu Lab), 1.17 (Polymaker Fiberon and 3DXTech), ISO 1183[2][1][4]1.34 (ISO 1183, 3DXTech) against 1.27 specific gravity on moulded plaques (ASTM D792, Stratasys) — the two suppliers disagree[3][5]
Typical priceUSD/kg1 kg-equivalent spools span 39–133; the middle of the market is about 80[2][6][7][8]1 kg-equivalent spools cluster near 298[9][10][11][12]
Price range across brandsUSD/kg39–133 across brands; IEMAI 3D 39, Bambu Lab 43, YXPOLYER 45, Polymaker Fiberon 80, 3DXTech CarbonX 83, Obsidian 133[2][6][13][9][7][8]220-392 across brands and formats; 3DXTech ThermaX PEI 9085 220 at 2 kg, 3D4Makers 270 at 2 kg, Fiberlogy 298 at 500 g, Kimya 321 at 500 g, IEMAI 3D 385 at 1 kg, 3DXTech CarbonX PEI 9085+CF 392[9][10][11][12][14]
Market availability1–5Stocked by most mainstream brands[2][6][9][13][7][8]Niche, a handful of specialist brands[9][10][11][12]
Spool sizes & diameters1.75 and 2.85 mm; 0.5, 0.75, 1 and 2 kg spools[6][9][2]1.75 and 2.85 mm; 250 g to 2 kg spools, plus Stratasys canisters[9][12][5]
Typical applicationsLoad-bearing brackets, tooling and drone frames that must hold strength above 150 °C[2][1]Aircraft interior parts and rail rolling stock, where the flame, smoke and toxicity rating is the requirement[3]
Printing Parameters
Nozzle temperature°C260–290 (Bambu Lab); 280–300 (Polymaker Fiberon)[2][1]Not documented
Bed temperature°C40–50 (Polymaker Fiberon)[1]130–140 (3DXTech)[3]
Enclosure / chamber requirement1–5Enclosure required (passive) — Bambu Lab specifies a 45–60 °C chamber, Polymaker room temperature[2][1]Actively heated chamber required[15][16]
Recommended chamber temperature°C45–60 (Bambu Lab); room temperature (Polymaker Fiberon)[2][1]Not documented
Bed surface & adhesion aidEngineering or high-temperature plate with glue (Bambu Lab)[2]Not documented
Maximum volumetric flow (mm³/s; see test conditions)mm³/s8 at Bambu Lab's 100 mm/s cap on a 0.4 mm nozzle at 0.2 mm layer; Polymaker rates its grade to 300 mm/s[2][1][17]Not documented
Warping tendency1–5Not documentedSevere — heated chamber needed[15]
Bed-adhesion difficulty1–5Needs a specific surface plus adhesive[2]Not documented
Stringing / oozing tendency1–5Moderate — retraction tuning needed[18]Not documented
Overall printing difficulty1–5Expert / industrial hardware only — enclosure, hardened nozzle, an 80 °C dry and a printer that can hold the filament dry throughout[2][1][19]Expert / industrial hardware only[15][16]
Extruder requirement0.6 mm nozzle recommended by Bambu Lab; 0.4 and 0.8 also supported[2]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required — Polymaker measures brass nozzle life at about 9 h on PA6-CF20 and recommends hardened steel or ruby[1]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[15]
Abrasiveness1–5Highly abrasive — standard CF composite; Polymaker puts brass nozzle life at roughly 9 h[1]Non-abrasive when unfilled[3]
Nozzle clog risk1–5Very high — frequent jams without careful setup; the combination of moisture and fibre is the worst case in the dataset[19][1]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[20]
Heat-creep / jam sensitivity1–5Moderate — good heatbreak cooling needed[21]Not documented
Hotend requirementHardened steel or ruby nozzle plus an all-metal hot end rated to 300 °C[1][2]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Very high (>2 %) — 2.35 % saturated at 25 °C / 55 % RH (Bambu Lab)[2]Not documented
Equilibrium moisture content at ~50 % RH%2.35 saturated at 25 °C / 55 % RH (Bambu Lab)[2]Not documented
Drying temperature & time80 °C for 8–12 h (Bambu Lab); 100 °C for 10 h (Polymaker Fiberon)[2][1]Not documented
Symptoms when wetPopping and cracking during extrusion, then hard-to-diagnose defects[22]Not documented
Effect of moisture on strengthPolymaker publishes dry and wet printed blocks for PA6-CF20 itself: at 5.30 % moisture tensile falls 109.3 → 54.7 MPa and modulus 8636 → 2508 MPa, while notched Charpy rises 11.0 → 35.6 kJ/m². Fibre reinforcement reduces but does not remove the effect[1][22]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[20]
Storage requirementSealed below 20 % RH with desiccant; often needs to stay in a dryer while printing[19]Not documented
Hydrolysis at melt temperaturePolymaker specifies an 80–100 °C dry and storage below 20 % RH; no molecular-weight loss figure is published, and the wet data it does publish is conditioning rather than melt hydrolysis[1][23]Not documented
Mechanical Properties
Tensile strength (XY)MPa102 ± 7 (Bambu Lab) and 109.3 ± 2.4 (Polymaker Fiberon, dry/annealed) printed XY, ISO 527; the Fiberon grade falls to 54.7 ± 1.1 conditioned to 5.30 % moisture; 3DXTech quotes 63 at break[2][1][4]63-77 at break (printed XZ, ASTM D638, Stratasys F900/F3300/Fortus 450mc, three tips and two colours); 54 (printed XY, ISO 527, 3DXTech)[5][3]
Young's modulusMPa4430 ± 310 (Bambu Lab) and 8636 ± 211 (Polymaker Fiberon, dry/annealed) printed XY, ISO 527; Fiberon falls to 2508 ± 83 conditioned; 3DXTech quotes 3800[2][1][4]2040-2540 (printed XZ, ASTM D638, Stratasys); 2050 (printed XY, ISO 527, 3DXTech)[5][3]
Elongation at break%5.8 ± 1.6 printed XY, ISO 527 (Bambu Lab); 3DXTech quotes 3 at break[2][4]5.4-9.1 at break (printed XZ, ASTM D638, Stratasys); 1.9-4.3 in ZX; 3DXTech quotes 3 (ISO 527)[5][3]
Flexural strengthMPa161.0 ± 3.9 printed XY dry, 64.9 ± 4.9 conditioned, ISO 178 (Polymaker Fiberon); 3DXTech quotes 84[1][4]104-116 at break (printed XZ, ASTM D790 Procedure A, Stratasys); 72-98 in ZX; 3DXTech quotes 90 (ISO 178)[5][3]
Flexural modulusMPa7038 ± 205 printed XY dry and 2286 ± 185 conditioned, ISO 178 (Polymaker Fiberon); 3DXTech quotes 3750[1][4]2400-2550 (printed XZ, ASTM D790, Stratasys F900 T16 and T16A) against 2120-2130 in ZX; 3DXTech quotes 2170 (ISO 178)[5][3]
Charpy impact, notchedkJ/m²11.0 ± 0.3 printed XY dry and 35.6 ± 1.2 conditioned, ISO 179 notched (Polymaker Fiberon)[1]Not documented
Other impact dataCharpy unnotched 24.0 ± 1.0 printed XY dry and 73.0 ± 2.0 conditioned, 7.5 ± 2.7 printed Z dry (Polymaker Fiberon); Bambu Lab 40.3 ± 2.5 unnotched, 13.4 ± 1.7 notched[1][2]Izod notched 88.5-140 J/m XZ against 37-80 J/m ZX; unnotched 647-2260 J/m XZ against 169-633 J/m ZX (printed, ASTM D256/D4812, Stratasys, across three printers and three tips)[5]
Layer adhesion / Z tensileMPa48 ± 6 (Bambu Lab) and 54.0 ± 5.2 (Polymaker Fiberon, dry) printed Z, ISO 527; Fiberon falls to 25.5 ± 1.2 conditioned[2][1]39-63 at break (printed ZX, ASTM D638, Stratasys); the low end is the F900 T16 baseline, the high end the F3300 N500 hot end[5]
Brittleness1–5Moderate[2][1]Brittle — snaps with little warning[3]
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell M88 / R117 on extruded PA66-GF30 stock (ASTM D785); no figure is published for a carbon-fibre nylon filament[24]Rockwell M110 / R126 on extruded PEI stock (ASTM D785)[25]
Creep resistance / sustained load1–5Good. Ensinger rates its PA66-CF30 injection-moulding compound for exceptional performance under both static and dynamic loading with 110 °C continuous service; in a printed part the fibre restrains the matrix, but conditioning to equilibrium moisture still softens it[26][22]Excellent — holds load for years. Printed ZX coupons keep 87 % of room-temperature tensile strength at 104 °C and 70 % at 132 °C (ASTM D638); extruded PEI stock is rated 170 °C long-term service[5][25]
Fatigue / repeated-flex resistance1–5Good. Ensinger states its PA66-CF30 compound has improved fatigue strength in tension, flexure and compression against unfilled and glass-filled PA66[26]Not documented
Elasticity / flexibility1–5Rigid[2]Rigid[3]
Z strength as % of XY%47 (Bambu Lab) to 49 (Polymaker Fiberon), printed[2][1]56-86 (Stratasys ZX against XZ tensile at break, ASTM D638, across F900/F3300/Fortus 450mc and T16/T20/T40A tips); 58 on the F900 T16 baseline[5]
Thermal Properties
HDT at 0.45 MPa°C186 (Bambu Lab) and 215 (Polymaker Fiberon), ISO 75 at 0.45 MPa[2][1]158 (printed XY, ISO 75 at 0.45 MPa, 3DXTech) to 178 (printed XY 178.2 and ZX 178.4, ASTM D648 Method B at 66 psi, Stratasys); moulded 176.9[3][5]
HDT at 1.8 MPa°C164 (Bambu Lab) and 173 (Polymaker Fiberon), ISO 75 at 1.8 MPa[2][1]170-173 (printed XY 170.2 and ZX 172.6, ASTM D648 Method B at 264 psi); moulded 172.9[5]
Glass transition (Tg)°C68 (Bambu Lab) to 74.2 (Polymaker Fiberon), DSC; 3DXTech quotes 70[2][1][4]177 (moulded plaque, ASTM D7426 inflection point, Stratasys); 186 (DSC, 3DXTech)[5][3][27]
Melting point / Vicat°C223 melting (Bambu Lab, DSC); Vicat 212 (ISO 306)[2]Not documented
Continuous service temperature°CBounded by heat deflection of 164–173 °C at 1.8 MPa; no loaded-bar service figure is published[2][1]170 long-term service on extruded PEI stock, converted from 338 °F; 200 short term[25]
Annealing response100 °C for 16 h (Polymaker Fiberon)[1]Not documented
Thermal expansion (CTE)µm/m·K94 in the XY direction and 180 in Z, measured on XY-built specimens (79 and 148 on XZ/ZX-built specimens), room temperature to 60 °C, ASTM E831. From Stratasys FDM Nylon-CF10, a blended-nylon matrix with 10 wt% carbon fibre — the closest published printed CTE for a carbon-fibre nylon[28]44.9 (printed XY, -50 to 80 °C, ASTM E831), falling to 31.4 over 80-160 °C; ZX gives 44.5 over -50 to 60 °C. Black pigment raises it to 51.9[5]
Flammability / UL 94Flammable; no UL 94 rating published[1]UL 94 V-0 at 1.5 mm on the base resin. Printed parts are tested to 14 CFR 25.853, BSS 7238 and 7239 and AITM 2.0007B and 3.0005 covering 60 s and 12 s vertical burn, 15 s horizontal burn, smoke density, toxic gas emission and OSU heat release[3][5]
Environment & Chemical
UV resistance1–5Months outdoors before embrittlement — unstabilised polyamide yellows and chalks under UV[18]Good — years with some colour shift. 1000 h of QUV cycling to ASTM G154 left printed ZX coupons at 55.5 MPa yield against 56.0 unexposed, with elongation and modulus unchanged[5]
Chemical resistanceWithstands oils, fuels and alkalis[18]Not documented
Water / humidity resistance in service1–5Absorbs water, properties shift[22]Not documented
Food contactNot food-contact certified[18]Not documented
Biodegradability / compostabilityNot biodegradable[18]Not documented
RecyclabilityFibre-filled polyamide is not accepted in household plastic collection[18]Not documented
Electrical & ESD propertiesSurface resistance above 10⁹ ohm/sq — not static-dissipative (3DXTech, ASTM D257)[4]Not documented
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[29]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[29]
VOC emission rateµg/minUp to 180 caprolactam, the dominant VOC from nylon and the largest single-VOC rate in the study[29]Not documented
Ultrafine-particle emission rateparticles/min≈2 × 10⁸ median for nylon — low for particles despite the highest VOC mass measured[29]Not documented
Hazardous species emittedCaprolactam, at up to 180 µg/min from nylon filament[29]Not documented
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[29]Ventilated room or enclosure recommended[29]
Dust & fibre handling hazardFibre is bound in the matrix; sanding dust should not be inhaled[1]Not documented
Post-Processing
Sanding & machiningSands to a matte finish; the fibre makes it cut more cleanly than unfilled nylon[21]Not documented
Gluing & solvent weldingCyanoacrylate; no common solvent welds polyamide[21]Not documented
Vapour / chemical smoothingNo practical vapour smoothing[21]Not documented
Support material pairingPolyDissolve S1 (Polymaker Fiberon)[1]Not documented
Dimensional accuracy & detailConditioned parts grow; Polymaker declines to publish a standard dimensional allowance because it depends on geometry and infill[22]Not documented
Solvents & Solubility
Soluble inFormic acid, phenol, m-cresol and hexafluoroisopropanol dissolve the matrix at 23 °C, leaving the fibre; laboratory reagents.[30]Chlorinated hydrocarbons — dichloromethane and chloroform — are solvents for polyetherimide. Laboratory reagents.[31][32]
Softened or crazed byZinc chloride solutions stress-crack the nylon matrix, alcoholic calcium chloride dissolves it, mineral acids attack it.[30]Acetone, MEK, benzene, toluene and butyl acetate craze or stress-crack it; alcohols, fuels and dilute acids do not.[32][31]
Solvent welding & smoothing agentNone — nylon's only solvents (formic acid, phenol, HFIP) degrade the part, and the fibre blocks surface flow anyway.[30]Dichloromethane is the only welding route, and it is a controlled carcinogen rather than a workshop material.[31][32]

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. Fiberon PA6-CF20 Technical Data Sheet V1.1 Polymaker · 2024-12 · tds
  2. Bambu Filament Technical Data Sheet — PA6-CF Bambu Lab · 2026-08 · tds
  3. ThermaX PEI 9085 Technical Data Sheet v4 3DXTech · 2026-08 · tds
  4. CarbonX Carbon Fiber Nylon (Gen3) Technical Data Sheet v3.0 3DXTech · 2026-08 · tds
  5. ULTEM 9085 Resin — FDM Material Data Sheet Stratasys · 2026-04 · tds
  6. Polymaker product catalogue Polymaker · 2026-08 · vendor
  7. YXPOLYER PA6 CF-Black 1 kg — product page YXPOLYER · 2026-08 · vendor
  8. IEMAI 3D CF-PA6 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  9. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  10. Kimya PEI-9085 Natural 2.85 mm 500 g igo3d · 2026-08 · vendor
  11. Fiberlogy PEI 9085 Natural, 1.75 mm / 500 g 3DJAKE · 2026-08 · vendor
  12. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  13. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  14. IEMAI 3D PEI 9085 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  15. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  16. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  17. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  18. PA (Nylon) — material basics Polymaker Wiki · 2026-08 · doc
  19. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  20. THERMAX PEI 9085 — product page (print recommendations) 3DXTech · 2026-08 · doc
  21. Nylon — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  22. Moisture Conditioning — effect on printed nylon properties Polymaker Wiki · 2026-08 · doc
  23. PolyMide CoPA Technical Data Sheet V5.4 (dry and wet status blocks) Polymaker · 2024-11 · tds
  24. TECAMID 66 GF30 black (PA66-GF30) — stock shape properties Ensinger · 2026-08 · tds
  25. TECAPEI natural (PEI) — stock shape properties Ensinger · 2026-08 · tds
  26. TECACOMP PA66 CF30 black — injection-moulding compound Ensinger · 2026-08 · tds
  27. ThermaX PEI 1010 Technical Data Sheet v4 3DXTech · 2026-08 · tds
  28. FDM Nylon-CF10 — Material Data Sheet (blended nylon, 10 wt% carbon fibre) Stratasys · 2026-08 · tds
  29. 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
  30. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  31. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  32. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds