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EG Carbon Brush vs Glassy Carbon

Ceramic · grade comparison

EG Carbon Brush and Glassy Carbon are both ceramic grades. Glassy Carbon is the stronger of the two: tensile strength 130 MPa (18.9 ksi) against 14 MPa (2.03 ksi) for EG Carbon Brush, about 9.3 times as much. Glassy Carbon is lighter (1.42 g/cm³ vs 1.65 g/cm³ for EG Carbon Brush) and Glassy Carbon is stiffer (35 GPa vs 10 GPa). On the shop floor, EG Carbon Brush machines more easily (excellent vs not recommended).

EG Carbon BrushChoose it when the part is machined in volume.

Glassy CarbonChoose it when strength drives the design, or when weight is the constraint.

EG Carbon Brush vs Glassy Carbon: properties

EG Carbon BrushGlassy Carbon

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

10 GPa1.5 Msi
35 GPa5.1 Msi

Shear Modulus

4.2 GPa0.61 Msi
14.5 GPa2.1 Msi

Tensile Strength (Ultimate)

14 MPa2 ksi
130 MPa18.9 ksi

Compressive Strength

45 MPa6.5 ksi
480 MPa69.6 ksi

Flexural Strength

28 MPa4.1 ksi
260 MPa37.7 ksi

Shear Strength

12 MPa1.7 ksi
60 MPa8.7 ksi

Fracture Toughness (K_IC)

1 MPa·√m0.91 ksi·√in
0.8 MPa·√m0.73 ksi·√in

Hardness, Mohs

1.5
6.5

Bulk Modulus

—
19 GPa2.8 Msi

Elongation at Break

—
0.4%

Hardness, Vickers

—
340 HV

Hardness, Knoop

—
320 HK

Same in both: Poisson's Ratio 0.2

Physical

Density and transition temperatures.

Density

1.65 g/cm³0.06 lb/in³
1.42 g/cm³0.05 lb/in³

Melting Point (Solidus)

3,650°C6,602 °F
—

Porosity

22%
0%

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
6.3 W/m·K3.6 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

4 µm/m·K2.2 µin/in·°F
2.6 µm/m·K1.4 µin/in·°F

Max Service Temperature (continuous)

350°C662 °F
600°C1,112 °F

Min Service Temperature

-50°C-58 °F
-269°C-452 °F

Same in both: Specific Heat Capacity 710 J/kg·K0.17 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Resistivity

4×10⁻⁵ Ω·m1,575 µΩ·in
4.5×10⁻⁵ Ω·m1,772 µΩ·in

Volume Resistivity

0 Ω·cm
0 Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

85 / 100
95 / 100

Manufacturability

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

Machinability

95 / 100
12 / 100

Polishability

35 / 100
95 / 100

Sintering / Firing Temperature

2,600°C4,712 °F
2,300°C4,172 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

130 MJ/kg55,890 BTU/lb
300 MJ/kg128,977 BTU/lb

Embodied Carbon (primary production)

9 kg CO₂/kg
22 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
150 L/kg18 gal/lb

Typical Recycled Content

5%
0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

8 kN·m/kg
92 kN·m/kg

Specific Stiffness (E / density)

6.1 MN·m/kg
24.6 MN·m/kg

Thermal Diffusivity

38.4 mm²/s
6.2 mm²/s

Thermal Shock Resistance Index

16
9

Strength versus weight

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

501002005001,000234567Density (g/cm³)Yield strength (MPa) — log scale

Manufacturing and finishing

CapabilityEG Carbon BrushGlassy Carbon
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

EG Carbon Brush vs Glassy Carbon — frequently asked

Is Glassy Carbon stronger than EG Carbon Brush?

Yes. Glassy Carbon has a typical tensile strength of 130 MPa (18.9 ksi) against 14 MPa (2.03 ksi) for EG Carbon Brush — about 9.3 times as much.

Which is cheaper, EG Carbon Brush or Glassy Carbon?

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

Which is easier to machine, EG Carbon Brush or Glassy Carbon?

EG Carbon Brush. Its machinability rates excellent (95/100) against not recommended (12/100) for Glassy Carbon.

Ready to make it?

Upload a CAD file and FabDigit prices the part in EG Carbon Brush and Glassy Carbon 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.