PET CF30 vs PET IM
Polymer · PET grade comparison
PET CF30 and PET IM are two grades of the same polymer grade, PET: CF30 (30% Carbon Fiber) versus IM (impact-modified / toughened PET). The chemistry is identical, so every difference below comes from the condition. PET IM is the stronger of the two: yield strength 100 MPa (14.5 ksi) against 80 MPa (11.6 ksi) for PET CF30, about 25% more. PET IM is the more ductile: elongation 5% versus 1.8% for PET CF30. PET CF30 is stiffer (21 GPa vs 6.5 GPa) and PET CF30 runs hotter in service (150°C vs 120°C continuous). On the shop floor, PET IM machines more easily (good vs fair) and PET IM welds better (fair vs poor).
PET CF30Choose it when the part sees heat.
PET IMChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
PET CF30 vs PET IM: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell M
Hardness, Rockwell R
Same in both: Shear Modulus 1.1 GPa0.16 Msi · Bulk Modulus 5 GPa0.65 Msi · Compressive Modulus 3 GPa0.44 Msi
Physical
Density and transition temperatures.
Density
Melting Temperature (Tm)
Water Absorption (24 h)
Water Absorption (Saturation)
Same in both: Glass Transition (Tg) 79°C174 °F · Refractive Index 1.575 · Light Transmission 88%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Electrical
Conductivity and insulation.
Electrical Resistivity
Volume Resistivity
Surface Resistivity
Same in both: Dielectric Strength 22 kV/mm559 V/mil · Dielectric Constant (1 MHz) 3.2 · Dissipation Factor (1 MHz) 0.018 · Comparative Tracking Index (CTI) 600 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Mold Shrinkage
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Same in both: Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Water 120 L/kg14.4 gal/lb
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.
PET CF30 vs PET IM — frequently asked
Is PET IM stronger than PET CF30?
Yes. PET IM has a typical yield strength of 100 MPa (14.5 ksi) against 80 MPa (11.6 ksi) for PET CF30 — about 25% more. Tensile strength is 105 MPa (15.2 ksi) vs 200 MPa (29 ksi).
Which grade does FabDigit quote by default, CF30 or IM?
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, PET CF30 or PET IM?
PET IM. Its machinability rates good (55/100) against fair (45/100) for PET CF30; for welding the order is PET IM first (fair, 35/100) then PET CF30 (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PET CF30 and PET IM 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.