PC/PET GF20 vs PC/PET GF30
Polymer · PC/PET grade comparison
PC/PET GF20 and PC/PET GF30 are two grades of the same polymer grade, PC/PET: GF20 (20 % glass-fiber reinforced) versus GF30 (30 % glass-fiber reinforced). The chemistry is identical, so every difference below comes from the condition. PC/PET GF30 is the stronger of the two: tensile strength 115 MPa (16.7 ksi) against 95 MPa (13.8 ksi) for PC/PET GF20, about 21% more. In exchange, PC/PET GF20 is the more ductile: elongation 5% versus 3.5% for PC/PET GF30. PC/PET GF20 is lighter (1.36 g/cm³ vs 1.43 g/cm³ for PC/PET GF30) and PC/PET GF30 is stiffer (7.5 GPa vs 5.2 GPa).
PC/PET GF20Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
PC/PET GF30Choose it when strength drives the design.
PC/PET GF20 vs PC/PET GF30: 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
Tensile Strength (Ultimate)
Elongation at Break
Flexural Strength
Flexural Modulus
Izod Impact, Notched
Same in both: Poisson's Ratio 0.4 · Yield Strength (0.2% offset) 53 MPa7.7 ksi · Compressive Strength 70 MPa10.2 ksi · Hardness, Rockwell M 72 HRM · Hardness, Rockwell R 118 HRR
Physical
Density and transition temperatures.
Density
Same in both: Melting Temperature (Tm) 250°C482 °F · Glass Transition (Tg) 140°C284 °F · Water Absorption (24 h) 0.15% · Water Absorption (Saturation) 0.4%
Thermal
How each material carries heat and how hot it can run.
Thermal Expansion (CTE, 20–100 °C)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Same in both: Thermal Conductivity 0.21 W/m·K0.12 BTU/hr·ft·°F · Specific Heat Capacity 1,300 J/kg·K0.31 BTU/lb·°F · Max Service Temperature (continuous) 100°C212 °F · Min Service Temperature -40°C-40 °F · Vicat Softening Point (B50) 138°C280 °F · Limiting Oxygen Index 26% · Max Service Temperature (short-term) 130°C266 °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) 3.1 · Dissipation Factor (1 MHz) 0.012 · Volume Resistivity 1×10¹⁶ Ω·cm · Surface Resistivity 1×10¹⁶ Ω · Comparative Tracking Index (CTI) 250 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: UV / Weathering Resistance 35 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Mold Shrinkage
Same in both: Weldability 70 / 100 · Polishability 55 / 100 · Melt Flow Rate 18 g/10 min · Processing Melt Temperature (typ.) 265°C509 °F · Mold Temperature (typ.) 75°C167 °F
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 105 MJ/kg45,142 BTU/lb · Embodied Carbon (primary production) 5.5 kg CO₂/kg · Embodied Water 300 L/kg35.9 gal/lb · Typical Recycled Content 20%
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.
PC/PET GF20 vs PC/PET GF30 — frequently asked
Is PC/PET GF30 stronger than PC/PET GF20?
Yes. PC/PET GF30 has a typical tensile strength of 115 MPa (16.7 ksi) against 95 MPa (13.8 ksi) for PC/PET GF20 — about 21% more.
Which grade does FabDigit quote by default, GF20 or GF30?
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, PC/PET GF20 or PC/PET GF30?
PC/PET GF20, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for PC/PET GF30.
Ready to make it?
Upload a CAD file and FabDigit prices the part in PC/PET GF20 and PC/PET 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.