Graphite Felt vs Impervious Graphite
Ceramic · grade comparison
Graphite Felt and Impervious Graphite are both ceramic grades. Impervious Graphite is the stronger of the two: tensile strength 25 MPa (3.63 ksi) against 0.3 MPa (0.0435 ksi) for Graphite Felt, about 83 times as much. In exchange, Graphite Felt is the more ductile: elongation 10% versus 0.3% for Impervious Graphite. Graphite Felt is lighter (0.1 g/cm³ vs 1.8 g/cm³ for Impervious Graphite) and Impervious Graphite is stiffer (12 GPa vs 0 GPa). On the shop floor, Graphite Felt machines more easily (excellent vs very good).
Graphite FeltChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Impervious GraphiteChoose it when strength drives the design.
Graphite Felt vs Impervious Graphite: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all ceramic grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all ceramic grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Graphite FeltImpervious Graphite
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Flexural Strength
Shear Strength
Poisson's Ratio
Fracture Toughness (K_IC)
Hardness, Vickers
Hardness, Mohs
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Porosity
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Min Service Temperature
Thermal Expansion (CTE, 20–100 °C)
Same in both: Specific Heat Capacity 710 J/kg·K0.17 BTU/lb·°F
Electrical
Conductivity and insulation.
Electrical Resistivity
Volume Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Sintering / Firing Temperature
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
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.
Manufacturing and finishing
| Capability | Graphite Felt | Impervious Graphite |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Graphite Felt vs Impervious Graphite — frequently asked
Is Impervious Graphite stronger than Graphite Felt?
Yes. Impervious Graphite has a typical tensile strength of 25 MPa (3.63 ksi) against 0.3 MPa (0.0435 ksi) for Graphite Felt — about 83 times as much.
Which is cheaper, Graphite Felt or Impervious Graphite?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Graphite Felt or Impervious Graphite?
Graphite Felt. Its machinability rates excellent (95/100) against very good (80/100) for Impervious Graphite.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Graphite Felt and Impervious Graphite 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.