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PI CF30 vs PI TPI

Polymer · PI grade comparison

PI CF30 and PI TPI are two grades of the same polymer grade, PI: CF30 (30% carbon-fiber reinforced polyimide) versus TPI (thermoplastic polyimide, injection-moldable). The chemistry is identical, so every difference below comes from the condition. PI CF30 is the stronger of the two: tensile strength 100 MPa (14.5 ksi) against 92 MPa (13.3 ksi) for PI TPI, about 9% more. In exchange, PI TPI is the more ductile: elongation 40% versus 2% for PI CF30. PI TPI is lighter (1.33 g/cm³ vs 1.45 g/cm³ for PI CF30) and PI CF30 is stiffer (12 GPa vs 2.9 GPa). On the shop floor, PI TPI machines more easily (good vs fair).

PI CF30Choose it when strength drives the design, or when the part sees heat.

PI TPIChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

PI CF30 vs PI TPI: properties

PI CF30PI TPI

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

12 GPa1.7 Msi
2.9 GPa0.42 Msi

Tensile Strength (Ultimate)

100 MPa14.5 ksi
92 MPa13.3 ksi

Elongation at Break

2%
40%

Flexural Strength

150 MPa21.8 ksi
125 MPa18.1 ksi

Flexural Modulus

11 GPa1.6 Msi
2.9 GPa0.42 Msi

Same in both: Shear Modulus 1.1 GPa0.16 Msi · Bulk Modulus 6 GPa0.8 Msi · Poisson's Ratio 0.41 · Compressive Strength 130 MPa18.9 ksi · Compressive Modulus 2.9 GPa0.42 Msi · Shear Strength 80 MPa11.6 ksi · Fracture Toughness (K_IC) 2 MPa·√m1.8 ksi·√in · Izod Impact, Notched 43 J/m0.81 ft·lbf/in · Hardness, Shore D 88 Shore D · Hardness, Rockwell M 105 HRM

Physical

Density and transition temperatures.

Density

1.45 g/cm³0.05 lb/in³
1.33 g/cm³0.05 lb/in³

Glass Transition (Tg)

385°C725 °F
250°C482 °F

Same in both: Water Absorption (24 h) 0.3% · Water Absorption (Saturation) 1.2% · Refractive Index 1.7

Thermal

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

Thermal Conductivity

1.2 W/m·K0.69 BTU/hr·ft·°F
0.29 W/m·K0.17 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

22 µm/m·K12.2 µin/in·°F
52 µm/m·K28.9 µin/in·°F

Max Service Temperature (continuous)

300°C572 °F
240°C464 °F

Heat Deflection Temp. @ 1.8 MPa

360°C680 °F
238°C460 °F

Same in both: Specific Heat Capacity 1,130 J/kg·K0.27 BTU/lb·°F · Min Service Temperature -240°C-400 °F · Heat Deflection Temp. @ 0.45 MPa 400°C752 °F · Limiting Oxygen Index 45% · Max Service Temperature (short-term) 480°C896 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Dielectric Strength 22 kV/mm559 V/mil · Dielectric Constant (1 MHz) 3.5 · Dissipation Factor (1 MHz) 0.0034 · Volume Resistivity 1×10¹⁶ Ω·cm · Surface Resistivity 1×10¹⁵ Ω

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Corrosion Resistance 85 / 100 · UV / Weathering Resistance 60 / 100

Manufacturability

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

Machinability

35 / 100
68 / 100

Same in both: Weldability 5 / 100 · Formability (cold) 15 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 290 MJ/kg124,678 BTU/lb · Embodied Carbon (primary production) 13 kg CO₂/kg · Embodied Water 600 L/kg71.9 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 scalePI

PI CF30 vs PI TPI — frequently asked

Is PI CF30 stronger than PI TPI?

Yes. PI CF30 has a typical tensile strength of 100 MPa (14.5 ksi) against 92 MPa (13.3 ksi) for PI TPI — about 9% more.

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

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, PI CF30 or PI TPI?

PI TPI. Its machinability rates good (68/100) against fair (35/100) for PI CF30.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PI CF30 and PI TPI 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.