PES CF30 vs PES GF20
Polymer · PES grade comparison
PES CF30 and PES GF20 are two grades of the same polymer grade, PES: CF30 (30 % carbon-fibre reinforced) versus GF20 (20 % glass-fibre reinforced). The chemistry is identical, so every difference below comes from the condition. PES CF30 is the stronger of the two: tensile strength 175 MPa (25.4 ksi) against 125 MPa (18.1 ksi) for PES GF20, about 40% more. In exchange, PES GF20 is the more ductile: elongation 3.5% versus 1.6% for PES CF30. PES CF30 is stiffer (19 GPa vs 7 GPa) and PES CF30 conducts heat better (0.7 W/m·K vs 0.23 W/m·K).
PES CF30Choose it when strength drives the design.
PES GF20Choose it when the part is bent, formed or impact-loaded.
PES CF30 vs PES GF20: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Elongation at Break
Flexural Strength
Flexural Modulus
Izod Impact, Notched
Hardness, Rockwell M
Same in both: Shear Modulus 0.95 GPa0.14 Msi · Bulk Modulus 4 GPa0.62 Msi · Poisson's Ratio 0.4 · Yield Strength (0.2% offset) 84 MPa12.2 ksi · Compressive Strength 100 MPa14.5 ksi · Compressive Modulus 2.6 GPa0.38 Msi · Shear Strength 62 MPa9 ksi · Fracture Toughness (K_IC) 2.6 MPa·√m2.4 ksi·√in · Hardness, Shore D 86 Shore D · Hardness, Rockwell R 122 HRR
Physical
Density and transition temperatures.
Density
Light Transmission
Same in both: Glass Transition (Tg) 225°C437 °F · Water Absorption (24 h) 0.43% · Water Absorption (Saturation) 2.1% · Refractive Index 1.65
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Heat Deflection Temp. @ 1.8 MPa
Same in both: Specific Heat Capacity 1,100 J/kg·K0.26 BTU/lb·°F · Max Service Temperature (continuous) 180°C356 °F · Min Service Temperature -100°C-148 °F · Heat Deflection Temp. @ 0.45 MPa 212°C414 °F · Vicat Softening Point (B50) 222°C432 °F · Limiting Oxygen Index 38% · Max Service Temperature (short-term) 220°C428 °F
Electrical
Conductivity and insulation.
Surface Resistivity
Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Dielectric Strength 16 kV/mm406 V/mil · Dielectric Constant (1 MHz) 3.5 · Dissipation Factor (1 MHz) 0.0035 · Volume Resistivity 1×10¹⁶ Ω·cm · Comparative Tracking Index (CTI) 150 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Corrosion Resistance 80 / 100 · UV / Weathering Resistance 25 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Mold Shrinkage
Same in both: Weldability 70 / 100 · Formability (cold) 55 / 100 · Polishability 70 / 100 · Melt Flow Rate 20 g/10 min · Processing Melt Temperature (typ.) 360°C680 °F · Mold Temperature (typ.) 150°C302 °F
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 145 MJ/kg62,339 BTU/lb · Embodied Carbon (primary production) 8 kg CO₂/kg · Embodied Water 300 L/kg35.9 gal/lb · Typical Recycled Content 0%
Strength versus weight
Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
PES CF30 vs PES GF20 — frequently asked
Is PES CF30 stronger than PES GF20?
Yes. PES CF30 has a typical tensile strength of 175 MPa (25.4 ksi) against 125 MPa (18.1 ksi) for PES GF20 — about 40% more.
Which grade does FabDigit quote by default, CF30 or GF20?
Specify the condition in the material field or the drawing note; FabDigit prices the quote for the state you call out.
Which is easier to machine, PES CF30 or PES GF20?
PES GF20, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for PES CF30.
Ready to make it?
Upload a CAD file and FabDigit prices the part in PES CF30 and PES GF20 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.