PETG · reinforced grade
PETG-GF
Properties of the GF condition, compared with the other PETG grades.
Pick when stiffness, creep resistance and lower shrinkage matter more than transparency or toughness.
What is PETG-GF?
PETG-GF is PETG in the GF grade — pick when stiffness, creep resistance and lower shrinkage matter more than transparency or toughness. PETG-GF has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 65 MPa (9.43 ksi) — weaker than 52% of polymer grades. Elongation at break is 3% and the elastic modulus is 5.5 GPa (0.798 Msi). PETG-GF has a density of 1.42 g/cm³ (0.0513 lb/in³), heavier than 82% of polymer grades. Its glass-transition temperature is 80°C (176 °F). Unfilled is the default condition FabDigit quotes; GF is available on request or by drawing note.
Advantages
- Low, predictable mold shrinkage — 0.2%, better than 95% of polymer grades
- Stiff — 5.5 GPa (0.798 Msi), better than 87% of polymer grades
- Forms and bends easily — 88/100, better than 85% of polymer grades
- Polishes to a fine finish — 72/100, better than 85% of polymer grades
- Readily welded — 80/100, better than 84% of polymer grades
Limitations
- Limited service temperature — 63°C (145 °F), worse than 85% of polymer grades
- Limited ductility — 3%, worse than 83% of polymer grades
- Heavy — 1.42 g/cm³ (0.0513 lb/in³), worse than 82% of polymer grades
PETG-GF properties
Typical room-temperature values for PETG-GF — 11 properties are specific to this condition; the rest are grade-level values shared by every PETG grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.
Physical6
PETG-GF has a density of 1.42 g/cm³ (0.0513 lb/in³), heavier than 82% of polymer grades. Its glass-transition temperature is 80°C (176 °F).
Mechanical12
PETG-GF has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 65 MPa (9.43 ksi) — weaker than 52% of polymer grades. Elongation at break is 3% and the elastic modulus is 5.5 GPa (0.798 Msi).
Thermal11
PETG-GF is rated for continuous service to 63°C (145 °F). It conducts heat at 0.2 W/m·K (0.116 BTU/hr·ft·°F), worse than 56% of polymer grades. Thermal expansion is 35 µm/m·K (19.4 µin/in·°F).
Electrical6
PETG-GF is an electrical insulator with a dielectric strength of 16 kV/mm (406.4 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 63% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of PETG-GF takes about 84 MJ of energy and emits 3.2 kg of CO₂ — less than 81% of polymer grades. Typical recycled content is 0%.
Manufacturability7
PETG-GF's machinability is good (65/100, better than 66% of polymer grades); weldability very good (80/100); formability excellent (88/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other PETG grades and fills
PETG is also supplied in 9 other conditions. The full side-by-side table is on the PETG overview.
- UnfilledDefaultDefault choice for transparent, tough, easily formed parts and general injection molding.50 MPa tensile
- GFPick when stiffness, creep resistance and lower shrinkage matter more than transparency or toughness.65 MPa tensile
- StandardPick for stock extruded sheet used in glazing, machine guards, signage and thermoforming.50 MPa yield
- CFPick for stiffer, more dimensionally stable printed parts with matte black finish; brittle and abrasive to nozzles.48 MPa tensile
- ESDPick for electronics handling trays, guards and cleanroom fixtures needing 10^6–10^9 Ω surface resistivity.45 MPa tensile
- As PrintedUse these de-rated values for FDM-printed PETG parts; expect 40–60% of molded strength in Z.38 MPa yield
Working with PETG-GF
Is PETG easy to machine?
Machines and routes well with sharp, polished, high-rake tools and air blast; keep feeds high and coolant/mist on to avoid gumming and edge crazing, and avoid stress at drilled holes.
Can PETG be welded?
Excellent hot-plate, hot-gas, ultrasonic and RF/high-frequency welding; solvent bonds with cyclohexanone/MEK-based cements and glues well with cyanoacrylate or two-part urethane.
Can PETG be formed, bent or molded?
Thermoforms at 120–160 °C with little pre-drying and cold-bends without stress-whitening; inject at 230–260 °C melt / 10–40 °C mold, dry pellets 4 h at 65 °C to prevent hydrolytic splay.
What surface finishes work on PETG?
Takes screen/digital printing, hard-coating and vacuum metallizing; edges can be sanded and buffed (flame polishing is riskier than for acrylic), and paint/adhesive systems must be solvent-checked for crazing.
PETG chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| terephthalate (PTA/DMT) repeat unitacid component of the copolyester backbone (mol basis) | 48 – 52 | 50 |
| 1,4-cyclohexanedimethanol (CHDM) unit~30 mol% of the glycol fraction; suppresses crystallinity (amorphous) | 12 – 20 | 16 |
| additives (stabilizers, colorants, UV/FRgrade dependent; fillers listed separately per variant | 0 – 15 | 1 |
| ethylene glycol unitglycol component balance | ≥ 30 (balance) | — |
PETG-GF — frequently asked
What is PETG-GF used for?
PETG-GF is typically used for transparent machine guards, retail displays and shelf fixtures, light-box and signage panels, food-contact parts and containers, bottles and medical device housings. In short: versatile tough plastic.
What is the yield strength of PETG-GF?
PETG-GF has a typical yield strength of 50 MPa (7.25 ksi) and a tensile strength of 65 MPa (9.43 ksi) — weaker than 52% of polymer grades. Strength varies by condition: see the 10 listed tempers.
Is PETG-GF easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Machines and routes well with sharp, polished, high-rake tools and air blast; keep feeds high and coolant/mist on to avoid gumming and edge crazing, and avoid stress at drilled holes.
Can PETG-GF be welded?
Yes — weldability is rated very good (80/100). Excellent hot-plate, hot-gas, ultrasonic and RF/high-frequency welding; solvent bonds with cyclohexanone/MEK-based cements and glues well with cyanoacrylate or two-part urethane.
What surface finishes work on PETG-GF?
Takes screen/digital printing, hard-coating and vacuum metallizing; edges can be sanded and buffed (flame polishing is riskier than for acrylic), and paint/adhesive systems must be solvent-checked for crazing.
Can PETG-GF be formed, bent or molded?
Thermoforms at 120–160 °C with little pre-drying and cold-bends without stress-whitening; inject at 230–260 °C melt / 10–40 °C mold, dry pellets 4 h at 65 °C to prevent hydrolytic splay.
What is the maximum service temperature of PETG-GF?
PETG-GF is rated for continuous use to about 63°C (145 °F), and briefly to 75°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in PETG-GF?
Yes — PETG-GF is available for CNC machining, sheet metal, injection molding and 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Eastman Eastar / Spectar copolyester (PETG) product data — Eastman Chemical (2023)
- SKYGREEN PETG resin grades data sheets — SK Chemicals (2022)
- CAMPUS plastics database — PETG copolyester ISO data sets — CWFG / CAMPUS (2024)
- ISO 527-2 / ISO 178 / ISO 75 / ISO 306 test methods — ISO (2019)
- ASTM D256 / D638 / D648 / D785 test methods — ASTM (2022)
- Ensinger / Curbell semi-finished PETG sheet technical data — Ensinger, Curbell Plastics (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.