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PA6/66 CF20 vs PA6/66 GF30

Polymer · PA6/66 grade comparison

PA6/66 CF20 and PA6/66 GF30 are two grades of the same polymer grade, PA6/66: CF20 (20% carbon fiber reinforced) versus GF30 (30% short glass fiber reinforced). The chemistry is identical, so every difference below comes from the condition. PA6/66 CF20 is the stronger of the two: tensile strength 190 MPa (27.6 ksi) against 175 MPa (25.4 ksi) for PA6/66 GF30, about 9% more. In exchange, PA6/66 GF30 is the more ductile: elongation 3.2% versus 2.5% for PA6/66 CF20. PA6/66 CF20 is lighter (1.24 g/cm³ vs 1.36 g/cm³ for PA6/66 GF30) and PA6/66 CF20 is stiffer (15 GPa vs 9.5 GPa). On the shop floor, PA6/66 CF20 welds better (very good vs good).

PA6/66 CF20Choose it when strength drives the design, or when weight is the constraint.

PA6/66 GF30Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

PA6/66 CF20 vs PA6/66 GF30: properties

PA6/66 CF20PA6/66 GF30

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

15 GPa2.2 Msi
9.5 GPa1.4 Msi

Tensile Strength (Ultimate)

190 MPa27.6 ksi
175 MPa25.4 ksi

Elongation at Break

2.5%
3.2%

Flexural Strength

95 MPa13.8 ksi
250 MPa36.3 ksi

Flexural Modulus

14 GPa2 Msi
8.8 GPa1.3 Msi

Izod Impact, Notched

75 J/m1.4 ft·lbf/in
105 J/m2 ft·lbf/in

Hardness, Rockwell M

78 HRM
95 HRM

Same in both: Shear Modulus 1 GPa0.15 Msi · Poisson's Ratio 0.39 · Yield Strength (0.2% offset) 72 MPa10.4 ksi · Compressive Strength 80 MPa11.6 ksi · Shear Strength 55 MPa8 ksi · Hardness, Shore D 80 Shore D · Hardness, Rockwell R 118 HRR

Physical

Density and transition temperatures.

Density

1.24 g/cm³0.04 lb/in³
1.36 g/cm³0.05 lb/in³

Same in both: Melting Temperature (Tm) 196°C385 °F · Glass Transition (Tg) 50°C122 °F · Water Absorption (24 h) 1.8% · Water Absorption (Saturation) 9.5%

Thermal

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

Thermal Conductivity

0.6 W/m·K0.35 BTU/hr·ft·°F
0.3 W/m·K0.17 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

18 µm/m·K10 µin/in·°F
28 µm/m·K15.6 µin/in·°F

Max Service Temperature (continuous)

90°C194 °F
120°C248 °F

Heat Deflection Temp. @ 0.45 MPa

165°C329 °F
215°C419 °F

Same in both: Specific Heat Capacity 1,700 J/kg·K0.41 BTU/lb·°F · Min Service Temperature -40°C-40 °F · Heat Deflection Temp. @ 1.8 MPa 205°C401 °F · Vicat Softening Point (B50) 180°C356 °F · Limiting Oxygen Index 24% · Max Service Temperature (short-term) 150°C302 °F

Electrical

Conductivity and insulation.

Surface Resistivity

100,000 Ω
1×10¹³ Ω

Same in both: Electrical Resistivity 1×10¹² Ω·m3.94×10¹⁹ µΩ·in · Dielectric Strength 25 kV/mm635 V/mil · Dielectric Constant (1 MHz) 3.4 · Dissipation Factor (1 MHz) 0.03 · Volume Resistivity 1×10¹⁴ Ω·cm · Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 60 / 100 · UV / Weathering Resistance 30 / 100

Manufacturability

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

Machinability

38 / 100
42 / 100

Weldability

78 / 100
60 / 100

Mold Shrinkage

0.3%
0.45%

Same in both: Formability (cold) 60 / 100 · Polishability 55 / 100 · Melt Flow Rate 25 g/10 min · Processing Melt Temperature (typ.) 260°C500 °F · Mold Temperature (typ.) 70°C158 °F

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 122 MJ/kg52,451 BTU/lb · Embodied Carbon (primary production) 7.5 kg CO₂/kg · Embodied Water 450 L/kg53.9 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 scalePA6/66

PA6/66 CF20 vs PA6/66 GF30 — frequently asked

Is PA6/66 CF20 stronger than PA6/66 GF30?

Yes. PA6/66 CF20 has a typical tensile strength of 190 MPa (27.6 ksi) against 175 MPa (25.4 ksi) for PA6/66 GF30 — about 9% more.

Which grade does FabDigit quote by default, CF20 or GF30?

Specify the condition in the material field or the drawing note; FabDigit prices the quote for the state you call out.

Which welds better, PA6/66 CF20 or PA6/66 GF30?

PA6/66 CF20. Its weldability rates very good (78/100) against good (60/100) for PA6/66 GF30.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PA6/66 CF20 and PA6/66 GF30 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.