FabDigitFabDigit

PC GF30 vs PC GF40

Polymer · PC grade comparison

PC GF30 and PC GF40 are two grades of the same polymer grade, PC: GF30 (30% glass fiber reinforced) versus GF40 (40% Glass Fiber). The chemistry is identical, so every difference below comes from the condition. PC GF40 is the stronger of the two: tensile strength 150 MPa (21.8 ksi) against 125 MPa (18.1 ksi) for PC GF30, about 20% more. In exchange, PC GF30 is the more ductile: elongation 3% versus 2% for PC GF40. PC GF30 is lighter (1.43 g/cm³ vs 1.52 g/cm³ for PC GF40) and PC GF40 is stiffer (11.5 GPa vs 7.8 GPa). On the shop floor, PC GF30 welds better (very good vs poor).

PC GF30Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

PC GF40Choose it when strength drives the design.

PC GF30 vs PC GF40: properties

PC GF30PC GF40

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

7.8 GPa1.1 Msi
11.5 GPa1.7 Msi

Tensile Strength (Ultimate)

125 MPa18.1 ksi
150 MPa21.8 ksi

Elongation at Break

3%
2%

Compressive Strength

80 MPa11.6 ksi
140 MPa20.3 ksi

Flexural Strength

165 MPa23.9 ksi
205 MPa29.7 ksi

Flexural Modulus

7.5 GPa1.1 Msi
11 GPa1.6 Msi

Izod Impact, Notched

100 J/m1.9 ft·lbf/in
120 J/m2.2 ft·lbf/in

Hardness, Rockwell M

70 HRM
93 HRM

Same in both: Shear Modulus 0.83 GPa0.12 Msi · Bulk Modulus 4 GPa0.51 Msi · Poisson's Ratio 0.38 · Yield Strength (0.2% offset) 63 MPa9.1 ksi · Compressive Modulus 2.4 GPa0.35 Msi · Shear Strength 41 MPa5.9 ksi · Fracture Toughness (K_IC) 2.2 MPa·√m2 ksi·√in · Hardness, Shore D 84 Shore D · Hardness, Rockwell R 120 HRR

Physical

Density and transition temperatures.

Density

1.43 g/cm³0.05 lb/in³
1.52 g/cm³0.05 lb/in³

Water Absorption (24 h)

0.15%
0.1%

Water Absorption (Saturation)

0.35%
0.3%

Same in both: Glass Transition (Tg) 147°C297 °F · Refractive Index 1.585 · Light Transmission 88%

Thermal

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

Thermal Conductivity

0.25 W/m·K0.14 BTU/hr·ft·°F
0.32 W/m·K0.18 BTU/hr·ft·°F

Specific Heat Capacity

1,200 J/kg·K0.29 BTU/lb·°F
1,100 J/kg·K0.26 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

22 µm/m·K12.2 µin/in·°F
17 µm/m·K9.4 µin/in·°F

Heat Deflection Temp. @ 0.45 MPa

152°C306 °F
150°C302 °F

Heat Deflection Temp. @ 1.8 MPa

148°C298 °F
146°C295 °F

Vicat Softening Point (B50)

146°C295 °F
152°C306 °F

Limiting Oxygen Index

26%
27%

Max Service Temperature (short-term)

145°C293 °F
160°C320 °F

Same in both: Max Service Temperature (continuous) 135°C275 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Dielectric Strength

22 kV/mm559 V/mil
28 kV/mm711 V/mil

Dielectric Constant (1 MHz)

2.9
3.6

Dissipation Factor (1 MHz)

0.01
0.008

Volume Resistivity

1×10¹⁶ Ω·cm
1×10¹⁵ Ω·cm

Comparative Tracking Index (CTI)

250 V
200 V

Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Surface Resistivity 1×10¹⁵ Ω

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

UV / Weathering Resistance

30 / 100
35 / 100

Same in both: Corrosion Resistance 55 / 100

Manufacturability

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

Weldability

70 / 100
30 / 100

Formability (cold)

75 / 100
10 / 100

Polishability

40 / 100
20 / 100

Processing Melt Temperature (typ.)

295°C563 °F
310°C590 °F

Mold Temperature (typ.)

90°C194 °F
110°C230 °F

Same in both: Machinability 45 / 100 · Mold Shrinkage 0.2% · Melt Flow Rate 10 g/10 min

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

105 MJ/kg45,142 BTU/lb
80 MJ/kg34,394 BTU/lb

Embodied Carbon (primary production)

6.3 kg CO₂/kg
5.2 kg CO₂/kg

Same in both: Embodied Water 250 L/kg30 gal/lb · Typical Recycled Content 5%

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 scalePC

PC GF30 vs PC GF40 — frequently asked

Is PC GF40 stronger than PC GF30?

Yes. PC GF40 has a typical tensile strength of 150 MPa (21.8 ksi) against 125 MPa (18.1 ksi) for PC GF30 — about 20% more.

Which grade does FabDigit quote by default, GF30 or GF40?

Specify the condition in the material field or the drawing note; FabDigit prices the quote for the state you call out.

Which welds better, PC GF30 or PC GF40?

PC GF30. Its weldability rates very good (70/100) against poor (30/100) for PC GF40.

Ready to make it?

Upload a CAD file and FabDigit prices the part in PC GF30 and PC GF40 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.