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Glassy Carbon vs MG Carbon Brush

Ceramic · grade comparison

Glassy Carbon and MG Carbon Brush are both ceramic grades. Glassy Carbon is the stronger of the two: tensile strength 130 MPa (18.9 ksi) against 20 MPa (2.9 ksi) for MG Carbon Brush, about 6.5 times as much. Glassy Carbon is harder — 340 HV against 12 HV for MG Carbon Brush — which matters for wear surfaces and threads. Glassy Carbon is lighter (1.42 g/cm³ vs 3.6 g/cm³ for MG Carbon Brush) and Glassy Carbon is stiffer (35 GPa vs 13 GPa). On the shop floor, MG Carbon Brush machines more easily (excellent vs not recommended).

Glassy CarbonChoose it when strength drives the design, or when surface hardness matters.

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

Glassy Carbon vs MG Carbon Brush: properties

Glassy CarbonMG Carbon Brush

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

35 GPa5.1 Msi
13 GPa1.9 Msi

Shear Modulus

14.5 GPa2.1 Msi
—

Bulk Modulus

19 GPa2.8 Msi
—

Poisson's Ratio

0.2
0.22

Tensile Strength (Ultimate)

130 MPa18.9 ksi
20 MPa2.9 ksi

Elongation at Break

0.4%
—

Compressive Strength

480 MPa69.6 ksi
80 MPa11.6 ksi

Flexural Strength

260 MPa37.7 ksi
35 MPa5.1 ksi

Shear Strength

60 MPa8.7 ksi
15 MPa2.2 ksi

Fracture Toughness (K_IC)

0.8 MPa·√m0.73 ksi·√in
—

Hardness, Vickers

340 HV
12 HV

Hardness, Knoop

320 HK
—

Hardness, Mohs

6.5
1.5

Physical

Density and transition temperatures.

Density

1.42 g/cm³0.05 lb/in³
3.6 g/cm³0.13 lb/in³

Porosity

0%
10%

Melting Point (Solidus)

—
1,083°C1,981 °F

Thermal

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

Thermal Conductivity

6.3 W/m·K3.6 BTU/hr·ft·°F
110 W/m·K63.6 BTU/hr·ft·°F

Specific Heat Capacity

710 J/kg·K0.17 BTU/lb·°F
470 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

2.6 µm/m·K1.4 µin/in·°F
10 µm/m·K5.6 µin/in·°F

Max Service Temperature (continuous)

600°C1,112 °F
200°C392 °F

Min Service Temperature

-269°C-452 °F
-50°C-58 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

4.5×10⁻⁵ Ω·m1,772 µΩ·in
5×10⁻⁷ Ω·m19.7 µΩ·in

Volume Resistivity

0 Ω·cm
5×10⁻⁵ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

95 / 100
50 / 100

Manufacturability

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

Machinability

12 / 100
85 / 100

Polishability

95 / 100
35 / 100

Sintering / Firing Temperature

2,300°C4,172 °F
850°C1,562 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

300 MJ/kg128,977 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

22 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

150 L/kg18 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

0%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

92 kN·m/kg
6 kN·m/kg

Specific Stiffness (E / density)

24.6 MN·m/kg
3.6 MN·m/kg

Thermal Diffusivity

6.2 mm²/s
65 mm²/s

Thermal Shock Resistance Index

9
17

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

CapabilityGlassy CarbonMG Carbon Brush
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Glassy Carbon vs MG Carbon Brush — frequently asked

Is Glassy Carbon stronger than MG Carbon Brush?

Yes. Glassy Carbon has a typical tensile strength of 130 MPa (18.9 ksi) against 20 MPa (2.9 ksi) for MG Carbon Brush — about 6.5 times as much.

Which is cheaper, Glassy Carbon or MG Carbon Brush?

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, Glassy Carbon or MG Carbon Brush?

MG Carbon Brush. Its machinability rates excellent (85/100) against not recommended (12/100) for Glassy Carbon.

Ready to make it?

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