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PEI CF30 vs PEI GF10

Polymer · PEI grade comparison

PEI CF30 and PEI GF10 are two grades of the same polymer grade, PEI: CF30 (30% carbon fiber reinforced PEI) versus GF10 (10% glass fiber reinforced). The chemistry is identical, so every difference below comes from the condition. PEI CF30 is the stronger of the two: tensile strength 200 MPa (29 ksi) against 120 MPa (17.4 ksi) for PEI GF10, about 67% more. In exchange, PEI GF10 is the more ductile: elongation 6% versus 1.8% for PEI CF30. PEI GF10 is lighter (1.34 g/cm³ vs 1.42 g/cm³ for PEI CF30) and PEI CF30 is stiffer (19 GPa vs 4.5 GPa). On the shop floor, PEI GF10 machines more easily (good vs fair).

PEI CF30Choose it when strength drives the design.

PEI GF10Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

PEI CF30 vs PEI GF10: properties

PEI CF30PEI GF10

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

19 GPa2.8 Msi
4.5 GPa0.65 Msi

Tensile Strength (Ultimate)

200 MPa29 ksi
120 MPa17.4 ksi

Elongation at Break

1.8%
6%

Flexural Strength

270 MPa39.2 ksi
175 MPa25.4 ksi

Flexural Modulus

17 GPa2.5 Msi
4.5 GPa0.65 Msi

Izod Impact, Notched

85 J/m1.6 ft·lbf/in
60 J/m1.1 ft·lbf/in

Hardness, Rockwell M

109 HRM
110 HRM

Same in both: Shear Modulus 1.2 GPa0.17 Msi · Bulk Modulus 4 GPa0.55 Msi · Poisson's Ratio 0.36 · Yield Strength (0.2% offset) 105 MPa15.2 ksi · Compressive Strength 140 MPa20.3 ksi · Compressive Modulus 3 GPa0.44 Msi · Shear Strength 85 MPa12.3 ksi · Fracture Toughness (K_IC) 3 MPa·√m2.7 ksi·√in · Hardness, Shore D 87 Shore D · Hardness, Rockwell R 125 HRR

Physical

Density and transition temperatures.

Density

1.42 g/cm³0.05 lb/in³
1.34 g/cm³0.05 lb/in³

Same in both: Glass Transition (Tg) 217°C423 °F · Water Absorption (24 h) 0.25% · Water Absorption (Saturation) 1.25% · Refractive Index 1.66 · Light Transmission 78%

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

0.6 W/m·K0.35 BTU/hr·ft·°F
0.22 W/m·K0.13 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

12 µm/m·K6.7 µin/in·°F
40 µm/m·K22.2 µin/in·°F

Heat Deflection Temp. @ 1.8 MPa

210°C410 °F
205°C401 °F

Same in both: Specific Heat Capacity 1,100 J/kg·K0.26 BTU/lb·°F · Max Service Temperature (continuous) 170°C338 °F · Min Service Temperature -50°C-58 °F · Heat Deflection Temp. @ 0.45 MPa 210°C410 °F · Vicat Softening Point (B50) 219°C426 °F · Limiting Oxygen Index 47% · Max Service Temperature (short-term) 200°C392 °F

Electrical

Conductivity and insulation.

Surface Resistivity

100,000 Ω
1×10¹⁶ Ω

Same in both: Electrical Resistivity 1×10¹⁵ Ω·m3.94×10²² µΩ·in · Dielectric Strength 33 kV/mm838 V/mil · Dielectric Constant (1 MHz) 3.15 · Dissipation Factor (1 MHz) 0.0013 · Volume Resistivity 1×10¹⁷ Ω·cm · Comparative Tracking Index (CTI) 175 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 85 / 100 · UV / Weathering Resistance 40 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

40 / 100
58 / 100

Mold Shrinkage

0.6%
0.4%

Same in both: Weldability 60 / 100 · Formability (cold) 45 / 100 · Polishability 70 / 100 · Melt Flow Rate 9 g/10 min · Processing Melt Temperature (typ.) 370°C698 °F · Mold Temperature (typ.) 150°C302 °F

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 230 MJ/kg98,882 BTU/lb · Embodied Carbon (primary production) 9 kg CO₂/kg · Embodied Water 400 L/kg47.9 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.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scalePEI

PEI CF30 vs PEI GF10 — frequently asked

Is PEI CF30 stronger than PEI GF10?

Yes. PEI CF30 has a typical tensile strength of 200 MPa (29 ksi) against 120 MPa (17.4 ksi) for PEI GF10 — about 67% more.

Which grade does FabDigit quote by default, CF30 or GF10?

Unfilled (1000) is the default PEI condition in the FabDigit quote flow (neither CF30 nor GF10). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, PEI CF30 or PEI GF10?

PEI GF10. Its machinability rates good (58/100) against fair (40/100) for PEI CF30.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PEI CF30 and PEI GF10 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.