RP Graphite Electrode vs UHP Graphite Electrode
Ceramic · grade comparison
RP Graphite Electrode and UHP Graphite Electrode are both ceramic grades. UHP Graphite Electrode is the stronger of the two: tensile strength 8 MPa (1.16 ksi) against 7 MPa (1.02 ksi) for RP Graphite Electrode, about 14% more. In exchange, RP Graphite Electrode is the more ductile: elongation 0.25% versus 0.18% for UHP Graphite Electrode. RP Graphite Electrode is lighter (1.56 g/cm³ vs 1.7 g/cm³ for UHP Graphite Electrode) and UHP Graphite Electrode is stiffer (12 GPa vs 9 GPa).
RP Graphite ElectrodeChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
UHP Graphite ElectrodeChoose it when strength drives the design, or when the part sees heat.
RP Graphite Electrode vs UHP 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.
RP Graphite ElectrodeUHP Graphite Electrode
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Flexural Strength
Shear Strength
Hardness, Vickers
Hardness, Mohs
Same in both: Fracture Toughness (K_IC) 1 MPa·√m0.91 ksi·√in
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)
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 710 J/kg·K0.17 BTU/lb·°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
Same in both: Machinability 90 / 100 · Sintering / Firing Temperature 2,900°C5,252 °F
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Water
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 6 kg CO₂/kg
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 | RP Graphite Electrode | UHP Graphite Electrode |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
RP Graphite Electrode vs UHP Graphite Electrode — frequently asked
Is UHP Graphite Electrode stronger than RP Graphite Electrode?
Yes. UHP Graphite Electrode has a typical tensile strength of 8 MPa (1.16 ksi) against 7 MPa (1.02 ksi) for RP Graphite Electrode — about 14% more.
Which is cheaper, RP Graphite Electrode or UHP Graphite Electrode?
Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose RP Graphite Electrode over UHP Graphite Electrode?
Pick RP Graphite Electrode when the part is bent, formed or impact-loaded, or when weight is the constraint. Pick UHP Graphite Electrode when strength drives the design, or when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in RP Graphite Electrode and UHP 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.