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G-3 vs L

Composite · grade comparison

G-3 and L are both composite grades. G-3 is the stronger of the two: tensile strength 250 MPa (36.3 ksi) against 95 MPa (13.8 ksi) for L, about 163% more. In exchange, L is the more ductile: elongation 1.8% versus 1.5% for G-3. L is lighter (1.36 g/cm³ vs 1.85 g/cm³ for G-3) and G-3 is stiffer (18 GPa vs 7.5 GPa). On the shop floor, L machines more easily (very good vs fair).

G-3Choose it when strength drives the design.

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

G-3 vs L: properties

G-3L

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

18 GPa2.6 Msi
7.5 GPa1.1 Msi

Shear Modulus

6.5 GPa0.94 Msi
2.8 GPa0.41 Msi

Poisson's Ratio

0.17
0.25

Tensile Strength (Ultimate)

250 MPa36.3 ksi
95 MPa13.8 ksi

Elongation at Break

1.5%
1.8%

Compressive Strength

310 MPa45 ksi
260 MPa37.7 ksi

Compressive Modulus

16 GPa2.3 Msi
7 GPa1 Msi

Flexural Strength

310 MPa45 ksi
125 MPa18.1 ksi

Flexural Modulus

18 GPa2.6 Msi
8 GPa1.2 Msi

Shear Strength

120 MPa17.4 ksi
100 MPa14.5 ksi

Izod Impact, Notched

480 J/m9 ft·lbf/in
58 J/m1.1 ft·lbf/in

Hardness, Rockwell M

110 HRM
108 HRM

Fracture Toughness (K_IC)

—
2 MPa·√m1.8 ksi·√in

Hardness, Rockwell R

—
120 HRR

Physical

Density and transition temperatures.

Density

1.85 g/cm³0.07 lb/in³
1.36 g/cm³0.05 lb/in³

Glass Transition (Tg)

160°C320 °F
155°C311 °F

Water Absorption (24 h)

1.2%
1.4%

Water Absorption (Saturation)

2.5%
4.5%

Thermal

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

Specific Heat Capacity

1,150 J/kg·K0.27 BTU/lb·°F
1,400 J/kg·K0.33 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

15 µm/m·K8.3 µin/in·°F
25 µm/m·K13.9 µin/in·°F

Max Service Temperature (continuous)

130°C266 °F
120°C248 °F

Min Service Temperature

-50°C-58 °F
-40°C-40 °F

Limiting Oxygen Index

40%
32%

Max Service Temperature (short-term)

180°C356 °F
150°C302 °F

Heat Deflection Temp. @ 1.8 MPa

—
150°C302 °F

Same in both: Thermal Conductivity 0.3 W/m·K0.17 BTU/hr·ft·°F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹⁰ Ω·m3.94×10¹⁷ µΩ·in
1×10⁹ Ω·m3.94×10¹⁶ µΩ·in

Dielectric Strength

14 kV/mm356 V/mil
10 kV/mm254 V/mil

Dissipation Factor (1 MHz)

0.04
0.06

Volume Resistivity

1×10¹² Ω·cm
1×10¹¹ Ω·cm

Surface Resistivity

1×10¹¹ Ω
1×10¹⁰ Ω

Same in both: Dielectric Constant (1 MHz) 6 · Comparative Tracking Index (CTI) 125 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

72 / 100
55 / 100

UV / Weathering Resistance

30 / 100
35 / 100

Manufacturability

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

Machinability

42 / 100
80 / 100

Polishability

25 / 100
45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

78 MJ/kg33,534 BTU/lb
90 MJ/kg38,693 BTU/lb

Embodied Carbon (primary production)

4.5 kg CO₂/kg
4.6 kg CO₂/kg

Embodied Water

190 L/kg22.8 gal/lb
—

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

135 kN·m/kg
70 kN·m/kg

Specific Stiffness (E / density)

9.7 MN·m/kg
5.5 MN·m/kg

Thermal Diffusivity

0.1 mm²/s
0.2 mm²/s

Same in both: Thermal Shock Resistance Index 0

Strength versus weight

Yield strength against density for every composite grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

1101001,000510Density (g/cm³)Yield strength (MPa) — log scale

Manufacturing and finishing

CapabilityG-3L
Default condition——
Relative cost$$$ Premium$$$ Premium
Min. machined wall——
Best machined surface——

G-3 vs L — frequently asked

Is G-3 stronger than L?

Yes. G-3 has a typical tensile strength of 250 MPa (36.3 ksi) against 95 MPa (13.8 ksi) for L — about 163% more.

Which is cheaper, G-3 or L?

Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, G-3 or L?

L. Its machinability rates very good (80/100) against fair (42/100) for G-3.

Ready to make it?

Upload a CAD file and FabDigit prices the part in G-3 and L 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.