PC/PBT GF15 vs PC/PBT GF30
Polymer · PC/PBT grade comparison
PC/PBT GF15 and PC/PBT GF30 are two grades of the same polymer grade, PC/PBT: GF15 (15 % glass-fiber reinforced) versus GF30 (30 % glass-fiber reinforced). The chemistry is identical, so every difference below comes from the condition. PC/PBT GF30 is the stronger of the two: tensile strength 115 MPa (16.7 ksi) against 85 MPa (12.3 ksi) for PC/PBT GF15, about 35% more. In exchange, PC/PBT GF15 is the more ductile: elongation 6% versus 3.5% for PC/PBT GF30. PC/PBT GF15 is lighter (1.31 g/cm³ vs 1.44 g/cm³ for PC/PBT GF30) and PC/PBT GF30 is stiffer (8 GPa vs 4.6 GPa).
PC/PBT GF15Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
PC/PBT GF30Choose it when strength drives the design, or when the part sees heat.
PC/PBT GF15 vs PC/PBT 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) 52 MPa7.5 ksi · Compressive Strength 70 MPa10.2 ksi · Hardness, Shore D 76 Shore D · Hardness, Rockwell R 115 HRR
Physical
Density and transition temperatures.
Density
Same in both: Melting Temperature (Tm) 222°C432 °F · Glass Transition (Tg) 130°C266 °F · Water Absorption (24 h) 0.12% · Water Absorption (Saturation) 0.4%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Same in both: Specific Heat Capacity 1,400 J/kg·K0.33 BTU/lb·°F · Min Service Temperature -40°C-40 °F · Vicat Softening Point (B50) 135°C275 °F · Limiting Oxygen Index 24% · Max Service Temperature (short-term) 130°C266 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Dielectric Strength 26 kV/mm660 V/mil · Dielectric Constant (1 MHz) 3.1 · Dissipation Factor (1 MHz) 0.012 · Volume Resistivity 1×10¹⁵ Ω·cm · Surface Resistivity 1×10¹⁵ Ω · Comparative Tracking Index (CTI) 275 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Corrosion Resistance 80 / 100 · UV / Weathering Resistance 55 / 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 15 g/10 min · Processing Melt Temperature (typ.) 260°C500 °F · Mold Temperature (typ.) 70°C158 °F
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 95 MJ/kg40,843 BTU/lb · Embodied Carbon (primary production) 5.5 kg CO₂/kg · Embodied Water 250 L/kg30 gal/lb · Typical Recycled Content 10%
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/PBT GF15 vs PC/PBT GF30 — frequently asked
Is PC/PBT GF30 stronger than PC/PBT GF15?
Yes. PC/PBT GF30 has a typical tensile strength of 115 MPa (16.7 ksi) against 85 MPa (12.3 ksi) for PC/PBT GF15 — about 35% more.
Which grade does FabDigit quote by default, GF15 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/PBT GF15 or PC/PBT GF30?
PC/PBT GF15, by a small margin. Both rate fair for machinability — 50/100 against 42/100 for PC/PBT GF30.
Ready to make it?
Upload a CAD file and FabDigit prices the part in PC/PBT GF15 and PC/PBT 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.