Amorphous Graphite vs RP Graphite Electrode
Ceramic · grade comparison
Amorphous Graphite and RP Graphite Electrode are both ceramic grades. RP Graphite Electrode is the stronger of the two: tensile strength 7 MPa (1.02 ksi) against 5 MPa (0.725 ksi) for Amorphous Graphite, about 40% more. RP Graphite Electrode is the more ductile: elongation 0.25% versus 0.2% for Amorphous Graphite, and RP Graphite Electrode is harder (32 HV vs 15 HV). RP Graphite Electrode is lighter (1.56 g/cm³ vs 2.25 g/cm³ for Amorphous Graphite) and RP Graphite Electrode is stiffer (9 GPa vs 7 GPa). On the shop floor, Amorphous Graphite sits in a lower cost tier (budget, $) than RP Graphite Electrode (standard, $$).
Amorphous GraphiteChoose it when cost is the deciding factor.
RP Graphite ElectrodeChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
Amorphous Graphite vs RP Graphite Electrode: 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.
Amorphous GraphiteRP Graphite Electrode
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
Fracture Toughness (K_IC)
Hardness, Vickers
Shear Modulus
Poisson's Ratio
Same in both: Hardness, Mohs 1.5
Physical
Density and transition temperatures.
Density
Porosity
Same in both: Melting Point (Solidus) 3,650°C6,602 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Same in both: Specific Heat Capacity 710 J/kg·K0.17 BTU/lb·°F · Max Service Temperature (continuous) 450°C842 °F · Min Service Temperature -200°C-328 °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.
Polishability
Sintering / Firing Temperature
Same in both: Machinability 90 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
Thermal Shock Resistance Index
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 | Amorphous Graphite | RP Graphite Electrode |
|---|---|---|
| Default condition | — | — |
| Relative cost | $ Budget | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Amorphous Graphite vs RP Graphite Electrode — frequently asked
Is RP Graphite Electrode stronger than Amorphous Graphite?
Yes. RP Graphite Electrode has a typical tensile strength of 7 MPa (1.02 ksi) against 5 MPa (0.725 ksi) for Amorphous Graphite — about 40% more.
Which is cheaper, Amorphous Graphite or RP Graphite Electrode?
Amorphous Graphite is the lower-cost material: it sits in the budget tier ($) while RP Graphite Electrode is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
When should I choose Amorphous Graphite over RP Graphite Electrode?
Pick Amorphous Graphite when cost is the deciding factor. Pick RP Graphite Electrode when strength drives the design, or when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Amorphous Graphite and RP Graphite Electrode 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.