3D Printing Info

Filament comparison

PETG-GF vs PLA-PHA

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

Glass-fibre polyester (PETG-GF / PET-GF) guidePLA/PHA blend guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PETG-GF comparisonsMore PLA-PHA comparisons
PETG-GF vs PLA-PHA — documented properties and sources
PropertyGlass-fibre polyester (PETG-GF / PET-GF)PETGPLA/PHA blendPLA
Market snapshot
Listing priceUSD/kg; dated snapshots$27.38/kg median; $18.99–$29.99/kg across 3 dated product listings$76.40/kg median; $76.40–$76.40/kg across 1 dated product listings
Identity & Market
Base polymer / chemistryGlass-fibre reinforced polyester. Polymaker's Fiberon PET-GF15 uses a PET rather than a PETG matrix and carries 15 wt% glass fibre[1]PLA blended with polyhydroxyalkanoate, a bacterially fermented bio-polyester[2]
Densityg/cm³1.43 (Fiberon PET-GF15, ISO 1183)[1]1.2 (ISO 1183)[2]
Typical priceUSD/kg1 kg spools cluster near 25[3][4]Not documented
Price range across brandsUSD/kg19–30 across brands; ELEGOO 19, Polymaker Fiberon 30[3][4]Not documented
Market availability1–5Niche, a handful of specialist brands[3][4]Niche, a handful of specialist brands[2][5]
Spool sizes & diameters1.75 mm; 0.5 and 1 kg spools[4]1.75 and 2.85 mm; 750 g and 2200 g spools[2]
Typical applicationsStiff, dimensionally stable fixtures; the Fiberon grade is designed to be annealed for heat resistance[1]General-purpose printing where PLA's brittleness is the limiting factor[2]
Printing Parameters
Nozzle temperature°CNot documented195–220 (colorFabb)[2]
Bed temperature°CNot documented50–60 (colorFabb)[2]
Enclosure / chamber requirement1–5Not documentedOpen frame is fine[2]
Part cooling fanNot documented0–100 %; colorFabb states the blend runs on both heated and unheated beds[2][6]
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[7][8]Not documented
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented3.2–8 at colorFabb's 40–100 mm/s, on a 0.4 mm nozzle at 0.2 mm layer[6][9]
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[7][8]Not documented
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[8]Not documented
Overall printing difficulty1–5Not documentedBeginner — prints on any machine out of the box[2]
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required[1]Brass fine indefinitely[2]
Abrasiveness1–5Highly abrasive — standard GF composite[1]Non-abrasive[2]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[10]Very low — unfilled PLA blend; Prusa lists no drybox and no hardened nozzle for PLA[11]
Heat-creep / jam sensitivity1–5Slightly sensitive[12]Not documented
Hotend requirementNo special hot-end required[12]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate (0.3–0.8 %) — the PETG matrix reaches 0.40 % saturated at 25 °C / 55 % RH; no glass-filled grade publishes its own figure[7]Moderate — the PLA matrix takes up 0.40–0.51 % saturated; colorFabb publishes no figure for the blend[13][14]
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[15]Not documented
Effect of moisture on strengthPolymaker 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[15]Polymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures for this grade; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[15]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[15][8]Not documented
Mechanical Properties
Tensile strength (XY)MPa59.9 ± 0.8 printed XY, ISO 527 (Fiberon PET-GF15)[1]62–64 (ISO 527-1A, colorFabb; two grades quoted)[2]
Young's modulusMPa4144 ± 133 printed XY, ISO 527 (Fiberon PET-GF15)[1]2960–3070 (ISO 527-1A, colorFabb)[2]
Elongation at break%4.0 ± 0.5 printed XY, ISO 527 (Fiberon PET-GF15)[1]4 and 11 (ISO 527-1A, colorFabb; two grades quoted)[2]
Flexural strengthMPa104.2 ± 2.4 printed XY, ISO 178 (Fiberon PET-GF15)[1]Not documented
Flexural modulusMPa3705 ± 85 printed XY, ISO 178 (Fiberon PET-GF15)[1]2500–3300 flexural modulus (ISO 178, colorFabb)[2]
Charpy impact, notchedkJ/m²8.7 ± 0.6 printed XY, ISO 179, notched (Fiberon PET-GF15)[1]2.8–3.7 (ISO 179, notched, colorFabb)[2]
Other impact dataCharpy unnotched 27.2 ± 2.0 printed XY (Fiberon PET-GF15, ISO 179)[1]Not documented
Layer adhesion / Z tensileMPa48.2 ± 0.3 printed Z, ISO 527 (Fiberon PET-GF15)[1]Not documented
Brittleness1–5Brittle — snaps with little warning; elongation 4.0 % in XY and 2.6 % in Z[1]Moderate — colorFabb positions the blend as tougher and less brittle than its generic PLA grades[2]
Creep resistance / sustained load1–5Below average — no GF-grade creep test; the CF grades sagged to 14.8–16.7 mm over 5 days at 1.25 kg against 17.1–20.4 mm unfilled[16][17][18]Poor — no PLA/PHA creep test; plain printed PLA sagged from 12 to 16.2–21.8 mm over 5 days at 1.25 kg[19][20][21]
Fatigue / repeated-flex resistance1–5Below average — no GF-grade S-N curve; elongation at break falls to 4.0 % in XY against 5.2–9.3 % unfilled[1][22]Below average — no S-N curve for the blend; colorFabb positions it as tougher and less brittle than its generic PLA, which ran 38 000–49 000 cycles at 30 % of tensile strength[22][2]
Elasticity / flexibility1–5Rigid[1]Rigid[2]
Z strength as % of XY%80 (Fiberon PET-GF15, printed Z against XY tensile)[1]Not documented
Thermal Properties
HDT at 0.45 MPa°C81.6 as printed, 133.7 after annealing (ISO 75, 0.45 MPa)[1]Not documented
HDT at 1.8 MPa°C71.8 as printed, 87.3 after annealing (ISO 75, 1.8 MPa)[1]Not documented
Glass transition (Tg)°C59.5 (DSC)[1]Not documented
Melting point / Vicat°C231.6 melting (DSC); Vicat 232.6 (ISO 306)[1]Above 155 melting (ISO 3146-C)[2]
Annealing responseAnnealing lifts HDT at 0.45 MPa from 81.6 to 133.7 °C[1]Not documented
Thermal expansion (CTE)µm/m·K20 along the print bead and 63–74 in the build direction at 30 °C (30 wt% GF, large-format printed, TMA)[23]Not documented
Flammability / UL 94UL 94 HB at 1.5 mm (Fiberon PET-GF15)[1]Not documented
Environment & Chemical
UV resistance1–5Not documentedDegrades within weeks outdoors[24]
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[8]Not documented
Food contactNot certified for food contact as filament[8]Not documented
Biodegradability / compostabilityNot biodegradable[8]colorFabb states the PHA component is 100 % biodegradable[2]
RecyclabilityNot accepted in household plastic collection[8]Not documented
Electrical & ESD propertiesSurface resistivity above 10¹² ohm — insulating (Fiberon PET-GF15, ANSI/ESD S11.11)[1]Not documented
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[25]Low hazard — minimal VOC and particle emission[25]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[25]None needed in a normal room[25]
Dust & fibre handling hazardGlass fibre is bound in the matrix; avoid inhaling sanding dust[1]Not documented
Post-Processing
Sanding & machiningSands poorly — the material is tough and gums rather than powders[12]Not documented
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[12]Not documented
Vapour / chemical smoothingNo practical vapour smoothing[12]Not documented
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[12]Not documented
Solvents & Solubility
Soluble inNo common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[26][27]Chloroform dissolves the PLA phase (10 % w/v, 2–4 h at 23 °C); THF and DMF need 65 °C. Laboratory reagents.[28]
Softened or crazed byAcetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[26]Acetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[28][27]
Solvent welding & smoothing agentDichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[27]Chloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[29][27]

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 PET-GF15 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  2. PLA/PHA technical data sheet colorFabb · 2026-08 · tds
  3. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  4. Polymaker product catalogue Polymaker · 2026-08 · vendor
  5. woodFill technical data sheet colorFabb · 2026-08 · tds
  6. glowFill technical data sheet colorFabb · 2026-08 · tds
  7. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  8. PETG — material basics Polymaker Wiki · 2026-08 · doc
  9. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  10. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  11. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  12. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  13. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  14. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  15. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  16. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  17. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  18. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  19. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  20. Polymaker PLA Pro vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  21. Carbon Fiber PLA vs META-PLA vs PLA+ vs PLA by Sunlu — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  22. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  23. Effects of Fiber Orientation on the Coefficient of Thermal Expansion of Fiber-Filled Polymer Systems in Large Format Polymer Extrusion-Based Additive Manufacturing Materials 15(8):2764 · 2022-04 · paper
  24. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  25. 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
  26. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  27. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  28. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  29. Effect of vapour smoothing in trichloromethane on 3D printed PLA — surface, mechanical and chemical structure Pitale, Keche & Chopra, Engineering Research Express 6(4) 045579 · 2024-12 · paper