FabDigit

Kevlar vs G11 and 2 more: properties

KevlarG11G7G5

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

76 GPa11 Msi
22 GPa3.2 Msi
14 GPa2 Msi
17 GPa2.5 Msi

Shear Modulus

2.2 GPa0.32 Msi
5.5 GPa0.8 Msi
6 GPa0.87 Msi

Poisson's Ratio

0.34
0.13
0.17
0.17

Tensile Strength (Ultimate)

1,350 MPa196 ksi
340 MPa49.3 ksi
170 MPa24.7 ksi
220 MPa31.9 ksi

Elongation at Break

1.8%
1.8%
1.5%

Compressive Strength

280 MPa40.6 ksi
450 MPa65.3 ksi
240 MPa34.8 ksi
415 MPa60.2 ksi

Compressive Modulus

70 GPa10.2 Msi
20 GPa2.9 Msi
12 GPa1.7 Msi
16 GPa2.3 Msi

Flexural Strength

620 MPa89.9 ksi
450 MPa65.3 ksi
172 MPa24.9 ksi
310 MPa45 ksi

Flexural Modulus

70 GPa10.2 Msi
22 GPa3.2 Msi
13 GPa1.9 Msi
18 GPa2.6 Msi

Shear Strength

58 MPa8.4 ksi
140 MPa20.3 ksi
95 MPa13.8 ksi
125 MPa18.1 ksi

Fracture Toughness (K_IC)

35 MPa·√m31.9 ksi·√in
20 MPa·√m18.2 ksi·√in
12 MPa·√m10.9 ksi·√in

Izod Impact, Notched

800 J/m15 ft·lbf/in
400 J/m7.5 ft·lbf/in
320 J/m6 ft·lbf/in
550 J/m10.3 ft·lbf/in

Hardness, Shore D

88 Shore D

Hardness, Rockwell M

110 HRM
100 HRM
115 HRM

Physical

Density and transition temperatures.

Density

1.38 g/cm³0.05 lb/in³
1.85 g/cm³0.07 lb/in³
1.8 g/cm³0.07 lb/in³
1.95 g/cm³0.07 lb/in³

Glass Transition (Tg)

135°C275 °F
150°C302 °F

Water Absorption (24 h)

0.6%
0.1%
0.2%
0.9%

Water Absorption (Saturation)

3.5%
0.35%
2%

Thermal

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

Thermal Conductivity

0.5 W/m·K0.29 BTU/hr·ft·°F
0.33 W/m·K0.19 BTU/hr·ft·°F
0.3 W/m·K0.17 BTU/hr·ft·°F
0.35 W/m·K0.2 BTU/hr·ft·°F

Specific Heat Capacity

1,400 J/kg·K0.33 BTU/lb·°F
1,100 J/kg·K0.26 BTU/lb·°F
1,000 J/kg·K0.24 BTU/lb·°F
1,100 J/kg·K0.26 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

-2 µm/m·K-1.1 µin/in·°F
14 µm/m·K7.8 µin/in·°F
12 µm/m·K6.7 µin/in·°F
14 µm/m·K7.8 µin/in·°F

Max Service Temperature (continuous)

120°C248 °F
180°C356 °F
220°C428 °F
150°C302 °F

Min Service Temperature

-196°C-321 °F
-196°C-321 °F
-60°C-76 °F
-60°C-76 °F

Heat Deflection Temp. @ 1.8 MPa

130°C266 °F
200°C392 °F
200°C392 °F

Limiting Oxygen Index

28%
22%
40%
45%

Max Service Temperature (short-term)

200°C392 °F
220°C428 °F
260°C500 °F
200°C392 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹² Ω·m3.94×10¹⁹ µΩ·in
1×10¹² Ω·m3.94×10¹⁹ µΩ·in
1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in
1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in

Dielectric Strength

18 kV/mm457 V/mil
16 kV/mm406 V/mil
15 kV/mm381 V/mil
15 kV/mm381 V/mil

Dielectric Constant (1 MHz)

4
5.2
4.2
7.5

Dissipation Factor (1 MHz)

0.018
0.02
0.003
0.03

Volume Resistivity

1×10¹⁴ Ω·cm
1×10¹⁴ Ω·cm
1×10¹³ Ω·cm
1×10¹³ Ω·cm

Surface Resistivity

1×10¹³ Ω
1×10¹² Ω
1×10¹² Ω

Comparative Tracking Index (CTI)

200 V
600 V
600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

80 / 100
88 / 100
80 / 100
58 / 100

UV / Weathering Resistance

25 / 100
45 / 100
75 / 100
45 / 100

Manufacturability

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

Machinability

20 / 100
45 / 100
35 / 100
25 / 100

Polishability

30 / 100
30 / 100
25 / 100
30 / 100

Weldability

0 / 100
0 / 100

Formability (cold)

3 / 100
5 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

250 MJ/kg107,481 BTU/lb
110 MJ/kg47,292 BTU/lb
110 MJ/kg47,292 BTU/lb
75 MJ/kg32,244 BTU/lb

Embodied Carbon (primary production)

14 kg CO₂/kg
7 kg CO₂/kg
7 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

200 L/kg24 gal/lb

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

978 kN·m/kg
184 kN·m/kg
94 kN·m/kg
113 kN·m/kg

Specific Stiffness (E / density)

55.1 MN·m/kg
11.9 MN·m/kg
7.8 MN·m/kg
8.7 MN·m/kg

Thermal Diffusivity

0.3 mm²/s
0.2 mm²/s
0.2 mm²/s
0.2 mm²/s

Thermal Shock Resistance Index

-4
0
0
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 scaleG11G7G5Kevlar

Manufacturing and finishing

CapabilityKevlarG11G7G5
Default conditionEpoxy MatrixEpoxy MatrixSilicone MatrixMelamine Matrix
Relative cost$$$ Premium$$$ Premium$$$ Premium$$$ Premium
Min. machined wall
Best machined surface

Both are offered for CNC machining and Sheet metal. Both take the same 1 finish: Painting.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Kevlar and G11 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.