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PP-B CF20 vs PP-B GF30

Polymer · PP-B grade comparison

PP-B CF20 and PP-B GF30 are two grades of the same polymer grade, PP-B: CF20 (20% carbon fiber reinforced) versus GF30 (30% coupled glass fiber). The chemistry is identical, so every difference below comes from the condition. PP-B CF20 is the stronger of the two: tensile strength 75 MPa (10.9 ksi) against 70 MPa (10.2 ksi) for PP-B GF30, about 7% more. In exchange, PP-B GF30 is the more ductile: elongation 3% versus 2.5% for PP-B CF20. PP-B CF20 is lighter (1.02 g/cm³ vs 1.13 g/cm³ for PP-B GF30) and PP-B GF30 is stiffer (6.2 GPa vs 1.2 GPa).

PP-B CF20Choose it when strength drives the design, or when weight is the constraint.

PP-B GF30Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

PP-B CF20 vs PP-B GF30: properties

PP-B CF20PP-B GF30

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

1.2 GPa0.17 Msi
6.2 GPa0.9 Msi

Tensile Strength (Ultimate)

75 MPa10.9 ksi
70 MPa10.2 ksi

Elongation at Break

2.5%
3%

Flexural Strength

33 MPa4.8 ksi
100 MPa14.5 ksi

Flexural Modulus

9 GPa1.3 Msi
5.8 GPa0.84 Msi

Izod Impact, Notched

60 J/m1.1 ft·lbf/in
110 J/m2.1 ft·lbf/in

Hardness, Rockwell R

78 HRR
100 HRR

Same in both: Shear Modulus 0.43 GPa0.06 Msi · Bulk Modulus 3 GPa0.46 Msi · Poisson's Ratio 0.42 · Yield Strength (0.2% offset) 24 MPa3.5 ksi · Compressive Strength 38 MPa5.5 ksi · Compressive Modulus 1.2 GPa0.17 Msi · Shear Strength 22 MPa3.2 ksi · Fracture Toughness (K_IC) 4 MPa·√m3.6 ksi·√in · Hardness, Shore D 66 Shore D

Physical

Density and transition temperatures.

Density

1.02 g/cm³0.04 lb/in³
1.13 g/cm³0.04 lb/in³

Same in both: Melting Temperature (Tm) 164°C327 °F · Glass Transition (Tg) -12°C10 °F · Water Absorption (24 h) 0.02% · Water Absorption (Saturation) 0.1% · Refractive Index 1.49

Thermal

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

Thermal Conductivity

0.21 W/m·K0.12 BTU/hr·ft·°F
0.27 W/m·K0.16 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

25 µm/m·K13.9 µin/in·°F
32 µm/m·K17.8 µin/in·°F

Max Service Temperature (continuous)

95°C203 °F
115°C239 °F

Heat Deflection Temp. @ 0.45 MPa

88°C190 °F
158°C316 °F

Heat Deflection Temp. @ 1.8 MPa

145°C293 °F
150°C302 °F

Same in both: Specific Heat Capacity 1,800 J/kg·K0.43 BTU/lb·°F · Min Service Temperature -30°C-22 °F · Vicat Softening Point (B50) 85°C185 °F · Limiting Oxygen Index 18% · Max Service Temperature (short-term) 120°C248 °F

Electrical

Conductivity and insulation.

Volume Resistivity

100,000 Ω·cm
1×10¹⁶ Ω·cm

Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Dielectric Strength 25 kV/mm635 V/mil · Dielectric Constant (1 MHz) 2.25 · Dissipation Factor (1 MHz) 4×10⁻⁴ · Surface Resistivity 1×10¹⁵ Ω · Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 90 / 100 · UV / Weathering Resistance 25 / 100

Manufacturability

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

Mold Shrinkage

0.3%
0.45%

Same in both: Machinability 50 / 100 · Weldability 88 / 100 · Formability (cold) 75 / 100 · Polishability 40 / 100 · Melt Flow Rate 8 g/10 min · Processing Melt Temperature (typ.) 230°C446 °F · Mold Temperature (typ.) 40°C104 °F

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 78 MJ/kg33,534 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 100 L/kg12 gal/lb · Typical Recycled Content 5%

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 scalePP-B

PP-B CF20 vs PP-B GF30 — frequently asked

Is PP-B CF20 stronger than PP-B GF30?

Yes. PP-B CF20 has a typical tensile strength of 75 MPa (10.9 ksi) against 70 MPa (10.2 ksi) for PP-B GF30 — about 7% 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.

When should I choose PP-B CF20 over PP-B GF30?

Pick PP-B CF20 when strength drives the design, or when weight is the constraint. Pick PP-B GF30 when the part is bent, formed or impact-loaded, or when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PP-B CF20 and PP-B 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.