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PEEK-450G vs PEEK-CF30

Polymer · grade comparison

PEEK-450G and PEEK-CF30 are both polymer grades. PEEK-CF30 is the stronger of the two: tensile strength 235 MPa (34.1 ksi) against 100 MPa (14.5 ksi) for PEEK-450G, about 135% more. In exchange, PEEK-450G is the more ductile: elongation 45% versus 1.7% for PEEK-CF30. PEEK-450G is lighter (1.3 g/cm³ vs 1.41 g/cm³ for PEEK-CF30) and PEEK-CF30 is stiffer (24 GPa vs 3.8 GPa). On the shop floor, PEEK-450G machines more easily (very good vs good) and PEEK-450G welds better (good vs fair).

PEEK-450GChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

PEEK-CF30Choose it when strength drives the design.

PEEK-450G vs PEEK-CF30: properties

PEEK-450GPEEK-CF30

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

3.8 GPa0.55 Msi
24 GPa3.5 Msi

Shear Modulus

1.4 GPa0.2 Msi
—

Bulk Modulus

5 GPa0.73 Msi
—

Tensile Strength (Ultimate)

100 MPa14.5 ksi
235 MPa34.1 ksi

Yield Strength (0.2% offset)

100 MPa14.5 ksi
—

Elongation at Break

45%
1.7%

Compressive Strength

125 MPa18.1 ksi
250 MPa36.3 ksi

Compressive Modulus

3.5 GPa0.51 Msi
16 GPa2.3 Msi

Flexural Strength

165 MPa23.9 ksi
340 MPa49.3 ksi

Flexural Modulus

4.1 GPa0.59 Msi
20 GPa2.9 Msi

Shear Strength

55 MPa8 ksi
95 MPa13.8 ksi

Fracture Toughness (K_IC)

6.5 MPa·√m5.9 ksi·√in
—

Izod Impact, Notched

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

Hardness, Shore D

85 Shore D
88 Shore D

Hardness, Rockwell M

99 HRM
105 HRM

Hardness, Rockwell R

126 HRR
—

Same in both: Poisson's Ratio 0.38

Physical

Density and transition temperatures.

Density

1.3 g/cm³0.05 lb/in³
1.41 g/cm³0.05 lb/in³

Water Absorption (24 h)

0.12%
0.08%

Water Absorption (Saturation)

0.45%
0.3%

Refractive Index

1.65
—

Same in both: Melting Temperature (Tm) 343°C649 °F · Glass Transition (Tg) 143°C289 °F

Thermal

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

Thermal Conductivity

0.25 W/m·K0.14 BTU/hr·ft·°F
0.9 W/m·K0.52 BTU/hr·ft·°F

Specific Heat Capacity

1,340 J/kg·K0.32 BTU/lb·°F
1,050 J/kg·K0.25 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

47 µm/m·K26.1 µin/in·°F
12 µm/m·K6.7 µin/in·°F

Max Service Temperature (continuous)

250°C482 °F
260°C500 °F

Heat Deflection Temp. @ 0.45 MPa

290°C554 °F
340°C644 °F

Heat Deflection Temp. @ 1.8 MPa

152°C306 °F
315°C599 °F

Same in both: Min Service Temperature -60°C-76 °F · Limiting Oxygen Index 35% · Max Service Temperature (short-term) 310°C590 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
100 Ω·m3.94×10⁹ µΩ·in

Dielectric Strength

20 kV/mm508 V/mil
—

Dielectric Constant (1 MHz)

3.2
—

Dissipation Factor (1 MHz)

0.003
—

Volume Resistivity

1×10¹⁶ Ω·cm
10,000 Ω·cm

Surface Resistivity

1×10¹⁶ Ω
100,000 Ω

Comparative Tracking Index (CTI)

150 V
—

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

UV / Weathering Resistance

40 / 100
70 / 100

Same in both: Corrosion Resistance 92 / 100

Manufacturability

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

Machinability

70 / 100
55 / 100

Weldability

55 / 100
35 / 100

Formability (cold)

35 / 100
10 / 100

Polishability

70 / 100
40 / 100

Mold Shrinkage

1.2%
0.3%

Processing Melt Temperature (typ.)

380°C716 °F
385°C725 °F

Same in both: Melt Flow Rate 3 g/10 min · Mold Temperature (typ.) 190°C374 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

290 MJ/kg124,678 BTU/lb
320 MJ/kg137,575 BTU/lb

Embodied Carbon (primary production)

16 kg CO₂/kg
18 kg CO₂/kg

Embodied Water

500 L/kg59.9 gal/lb
450 L/kg53.9 gal/lb

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

77 kN·m/kg
167 kN·m/kg

Specific Stiffness (E / density)

2.9 MN·m/kg
17 MN·m/kg

Thermal Diffusivity

0.1 mm²/s
0.6 mm²/s

Thermal Shock Resistance Index

0
1

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 scalePEEK-450G

Manufacturing and finishing

CapabilityPEEK-450GPEEK-CF30
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

PEEK-450G vs PEEK-CF30 — frequently asked

Is PEEK-CF30 stronger than PEEK-450G?

Yes. PEEK-CF30 has a typical tensile strength of 235 MPa (34.1 ksi) against 100 MPa (14.5 ksi) for PEEK-450G — about 135% more.

Which is cheaper, PEEK-450G or PEEK-CF30?

Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, PEEK-450G or PEEK-CF30?

PEEK-450G. Its machinability rates very good (70/100) against good (55/100) for PEEK-CF30; for welding the order is PEEK-450G first (good, 55/100) then PEEK-CF30 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in PEEK-450G and PEEK-CF30 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.