PETG-CF CF20
Reinforced grade · default condition
also CF PETG, PETG CF
CF20 = ~15–20 wt% chopped carbon fiber
Default commercial PETG-CF filament: best balance of stiffness, matte finish and printability on a hardened 0.4–0.6 mm nozzle.
Values for the CF20 condition
Other PETG-CF grades and fills
PETG-CF is listed in 5 conditions; see the grade overview at PETG-CF.
Compare all 5 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
RPETG-CF | Cost- and footprint-driven choice for non-critical prints; expect wider batch-to-batch spread in strength, colour and diameter. | 43 | 45 | 3.5 | 78 Shore D |
Static-dissipative PETG-CF | Use for electronics trays, ATE fixtures and cleanroom tooling where surface resistivity must sit in the 10^6–10^9 Ω dissipative window. | 46 | 48 | 3 | 79 Shore D |
~5–10 wt% carbon fiber | Pick when you want the matte CF look and reduced warping but need more ductility and gentler nozzle wear. | 48 | 9 | ||
CF20DefaultThis page ~15–20 wt% chopped carbon fiber | Default commercial PETG-CF filament: best balance of stiffness, matte finish and printability on a hardened 0.4–0.6 mm nozzle. | 52 | 4.5 | ||
~25–30 wt% carbon fiber | Choose for maximum stiffness and dimensional stability in jigs, fixtures and drone/RC frames; accept brittle behaviour and fast nozzle wear. | 56 | 2.2 |
What is PETG-CF CF20?
PETG-CF CF20 is PETG-CF in the CF20 grade — default commercial PETG-CF filament: best balance of stiffness, matte finish and printability on a hardened 0.4–0.6 mm nozzle. PETG-CF CF20 has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 52 MPa (7.54 ksi) — stronger than 52% of polymer grades. Elongation at break is 4.5% and the elastic modulus is 4.2 GPa (0.609 Msi). PETG-CF CF20 has a density of 1.32 g/cm³ (0.0477 lb/in³), heavier than 72% of polymer grades. Its glass-transition temperature is 79°C (174 °F).
Advantages
- Low, predictable mold shrinkage — 0.3%, better than 90% of polymer grades
- Stiff — 4.2 GPa (0.609 Msi), better than 87% of polymer grades
- Conducts heat well — 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades
Limitations
- Hard to polish — 30/100, worse than 82% of polymer grades
- Limited service temperature — 68°C (154 °F), worse than 80% of polymer grades
- High embodied carbon — 7 kg CO₂/kg, worse than 77% of polymer grades
- Limited ductility — 4.5%, worse than 75% of polymer grades
PETG-CF CF20 properties
Typical room-temperature values for PETG-CF CF20; 11 are specific to this condition. Other listed values are PETG-CF reference data and may not represent this condition. Bars are the position among polymer grades.
Physical4
PETG-CF CF20 has a density of 1.32 g/cm³ (0.0477 lb/in³), heavier than 72% of polymer grades. Its glass-transition temperature is 79°C (174 °F).
Mechanical13
PETG-CF CF20 has a yield strength of 50 MPa (7.25 ksi) and a tensile strength of 52 MPa (7.54 ksi) — stronger than 52% of polymer grades. Elongation at break is 4.5% and the elastic modulus is 4.2 GPa (0.609 Msi).
Thermal11
PETG-CF CF20 is rated for continuous service to 68°C (154 °F). It conducts heat at 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades. Thermal expansion is 40 µm/m·K (22.2 µin/in·°F).
Electrical2
Chemical & Environmental3
Corrosion resistance is very good (78/100), worse than 61% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of PETG-CF CF20 takes about 110 MJ of energy and emits 7 kg of CO₂ — more than 64% of polymer grades. Typical recycled content is 5%.
Manufacturability8
PETG-CF CF20's machinability is good (62/100, better than 60% of polymer grades); weldability fair (45/100); formability poor (25/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with PETG-CF CF20
Is PETG-CF easy to machine?
Drills, mills and taps easily at high speed with sharp carbide and light feeds; carbon fiber is abrasive and dust should be extracted, and keep tools cool to avoid smearing near Tg.
Can PETG-CF be welded?
Hot-plate, hot-gas and ultrasonic welding work on the matrix but fiber at the joint cuts strength; solvent/adhesive bonding needs sanding plus cyanoacrylate or epoxy since PETG resists most solvents.
Can PETG-CF be formed, bent or molded?
Print at 240–260 °C nozzle / 70–85 °C bed with a hardened steel or ruby nozzle ≥0.4 mm, dry the filament 4–6 h at 65 °C, and use slow first layers and generous cooling; injection molding requires drying and low shear to preserve fiber length.
What surface finishes work on PETG-CF?
Comes out matte black and hides layer lines well; sand or bead-blast for uniformity, avoid solvent vapor smoothing (PETG does not respond), and paint only after abrasion plus adhesion primer.
PETG-CF 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 |
|---|---|---|
| carbon fiber (chopped/milled PAN-based)primary reinforcement; sets stiffness and abrasiveness | 5 – 30 | 18 |
| processing aids / lubricants / pigmentdispersants, chain extenders, carbon black for colour | 0.5 – 3 | 1.5 |
| PETG (glycol-modified PET copolyester, Camorphous copolyester matrix | ≥ 70 (balance) |
PETG-CF CF20 — frequently asked
What is PETG-CF CF20 used for?
PETG-CF CF20 is typically used for functional brackets, enclosures and tooling. In short: stiff carbon-filled PETG.
What is the yield strength of PETG-CF CF20?
PETG-CF CF20 has a typical yield strength of 50 MPa (7.25 ksi) and a tensile strength of 52 MPa (7.54 ksi) — stronger than 52% of polymer grades. Strength varies by condition: see the 5 listed tempers.
Is PETG-CF CF20 easy to machine?
Reasonably — machinability is rated good (62/100, better than 60% of polymer grades). Drills, mills and taps easily at high speed with sharp carbide and light feeds; carbon fiber is abrasive and dust should be extracted, and keep tools cool to avoid smearing near Tg.
Can PETG-CF CF20 be welded?
With care — weldability is rated fair (45/100). Hot-plate, hot-gas and ultrasonic welding work on the matrix but fiber at the joint cuts strength; solvent/adhesive bonding needs sanding plus cyanoacrylate or epoxy since PETG resists most solvents.
What surface finishes work on PETG-CF CF20?
Comes out matte black and hides layer lines well; sand or bead-blast for uniformity, avoid solvent vapor smoothing (PETG does not respond), and paint only after abrasion plus adhesion primer.
Can PETG-CF CF20 be formed, bent or molded?
Print at 240–260 °C nozzle / 70–85 °C bed with a hardened steel or ruby nozzle ≥0.4 mm, dry the filament 4–6 h at 65 °C, and use slow first layers and generous cooling; injection molding requires drying and low shear to preserve fiber length.
What is the maximum service temperature of PETG-CF CF20?
PETG-CF CF20 is rated for continuous use to about 68°C (154 °F), and briefly to 85°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between PETG-CF CF20 and PETG-CF R?
CF20 is the default condition — default commercial PETG-CF filament: best balance of stiffness, matte finish and printability on a hardened 0.4–0.6 mm nozzle. R: cost- and footprint-driven choice for non-critical prints; expect wider batch-to-batch spread in strength, colour and diameter. Yield strength is 50 MPa in CF20 versus 43 MPa in R.
Can FabDigit make parts in PETG-CF CF20?
Yes — PETG-CF CF20 is available for 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- PETG-CF filament technical data sheet — Bambu Lab (2024)
- CarbonX PETG+CF carbon fiber PETG filament TDS — 3DXTech (2023)
- PETG-CF / PolyLite PETG technical data — Polymaker (2024)
- Eastar / Eastman copolyester (PETG) product data — Eastman Chemical (2022)
- Copolyester and short-fiber compound property records — CAMPUS Plastics (2024)
- ASTM D638 / D790 / D256 test methods for plastics — ASTM International (2022)
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.