Extruded Graphite EG-HP
Grade
EG-HP = halogen-purified extruded graphite
Use for semiconductor, PV, sintering and vacuum-furnace hot zones where metallic contamination must be avoided.
Values for the EG-HP condition
Other Extruded Graphite tempers and conditions
Extruded Graphite is listed in 4 conditions; see the grade overview at Extruded Graphite.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Coarse-grain extruded graphite | Cheapest large-diameter stock (electrode-type); choose when conductivity and size matter more than strength or surface finish. | — | 6 | — | — | 150 W/m·K |
EG-MDefault Medium-grain extruded graphite | General-purpose extruded stock for furnace parts, moulds, heating elements and rough EDM — best balance of price, size availability and strength. | — | 9 | — | — | 130 W/m·K |
EG-HPThis page Halogen-purified extruded graphite | Use for semiconductor, PV, sintering and vacuum-furnace hot zones where metallic contamination must be avoided. | — | 9 | 0.25 | 35 HV | 135 W/m·K |
Fine-grain extruded graphite | Pick when detail features, tighter tolerance or higher strength are needed but isostatic grades are too expensive. | — | 14 | — | — | 110 W/m·K |
What is Extruded Graphite EG-HP?
Extruded Graphite EG-HP is Extruded Graphite in the EG-HP grade — use for semiconductor, PV, sintering and vacuum-furnace hot zones where metallic contamination must be avoided. Extruded Graphite EG-HP has a tensile strength of 9 MPa (1.31 ksi), weaker than 92% of ceramic grades. Elongation at break is 0.25% and the elastic modulus is 10 GPa (1.45 Msi). Extruded Graphite EG-HP has a density of 1.7 g/cm³ (0.0614 lb/in³), lighter than 93% of ceramic grades. It melts at 3,650°C (6,602 °F). EG-M is the default condition FabDigit quotes; EG-HP is available on request or by drawing note.
Advantages
- High service temperature — 3,000°C (5,432 °F), better than 100% of ceramic grades
- Lightweight — 1.7 g/cm³ (0.0614 lb/in³), better than 93% of ceramic grades
- Conducts heat well — 135 W/m·K (78 BTU/hr·ft·°F), better than 92% of ceramic grades
- Easy to machine — 88/100, better than 92% of ceramic grades
- Ductile — tolerates forming and impact — 0.25%, better than 85% of ceramic grades
Limitations
- Hard to polish — 20/100, worse than 99% of ceramic grades
- Low stiffness — 10 GPa (1.45 Msi), worse than 93% of ceramic grades
- Low fracture toughness — 1 MPa·√m (0.91 ksi·√in), worse than 84% of ceramic grades
Extruded Graphite EG-HP properties
Typical room-temperature values for Extruded Graphite EG-HP; 14 are specific to this condition. Other listed values are Extruded Graphite reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical3
Extruded Graphite EG-HP has a density of 1.7 g/cm³ (0.0614 lb/in³), lighter than 93% of ceramic grades. It melts at 3,650°C (6,602 °F).
Mechanical10
Extruded Graphite EG-HP has a tensile strength of 9 MPa (1.31 ksi), weaker than 92% of ceramic grades. Elongation at break is 0.25% and the elastic modulus is 10 GPa (1.45 Msi).
Thermal5
Extruded Graphite EG-HP is rated for continuous service to 3,000°C (5,432 °F). It conducts heat at 135 W/m·K (78 BTU/hr·ft·°F), better than 92% of ceramic grades. Thermal expansion is 2.2 µm/m·K (1.22 µin/in·°F).
Electrical2
Extruded Graphite EG-HP has an electrical resistivity of 7.5×10⁻⁶ Ω·m.
Chemical & Environmental2
Corrosion resistance is excellent (85/100), better than 69% of ceramic grades.
Sustainability4
Producing a kilogram of Extruded Graphite EG-HP takes about 120 MJ of energy and emits 7.5 kg of CO₂ — more than 51% of ceramic grades. Typical recycled content is 5%.
Manufacturability3
Extruded Graphite EG-HP's machinability is excellent (88/100, better than 92% of ceramic grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Extruded Graphite EG-HP
Is Extruded Graphite easy to machine?
Cuts very easily dry with carbide or PCD tooling at high speed — never use coolant; conductive abrasive dust demands full vacuum extraction and sealed spindles, and sharp edges chip readily.
Can Extruded Graphite be welded?
Not weldable; parts are joined by graphite cement/carbonaceous adhesive, threaded graphite fittings or mechanical clamping.
Can Extruded Graphite be formed, bent or molded?
Formed only at the green stage by paste extrusion, then baked ~1000 °C and graphitised 2600–3000 °C; finished stock is brittle and must be net-machined, not bent or formed.
What surface finishes work on Extruded Graphite?
Optional halogen purification, pyrolytic-carbon/SiC coating or resin/pitch impregnation to seal porosity; surface can be blasted or lapped but coarse grain limits attainable Ra.
Extruded Graphite chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| ash≤10 ppm (0.001 %) for halogen-purified grades | 0.02 – 0.5 | 0.2 |
| Sresidual sulphur from coke | ≤ 0.05 | 0.02 |
| Cpetroleum/needle coke aggregate + coal-tar pitch binder, graphitised | ≥ 99 (balance) | — |
Extruded Graphite EG-HP — frequently asked
What is Extruded Graphite EG-HP used for?
Extruded Graphite EG-HP is typically used for electrodes, crucibles, heating elements and bushings. In short: lowest-cost graphite stock; large-section coarse-grain blanks; anisotropic extruded structure.
What is the tensile strength of Extruded Graphite EG-HP?
Extruded Graphite EG-HP has a typical tensile strength of 9 MPa (1.31 ksi) — weaker than 92% of ceramic grades. Strength varies by condition: see the 4 listed tempers.
Is Extruded Graphite EG-HP easy to machine?
Yes — machinability is rated excellent (88/100, better than 92% of ceramic grades). Cuts very easily dry with carbide or PCD tooling at high speed — never use coolant; conductive abrasive dust demands full vacuum extraction and sealed spindles, and sharp edges chip readily.
Can Extruded Graphite EG-HP be welded?
Not weldable; parts are joined by graphite cement/carbonaceous adhesive, threaded graphite fittings or mechanical clamping.
What surface finishes work on Extruded Graphite EG-HP?
Optional halogen purification, pyrolytic-carbon/SiC coating or resin/pitch impregnation to seal porosity; surface can be blasted or lapped but coarse grain limits attainable Ra.
Can Extruded Graphite EG-HP be formed, bent or molded?
Formed only at the green stage by paste extrusion, then baked ~1000 °C and graphitised 2600–3000 °C; finished stock is brittle and must be net-machined, not bent or formed.
What is the maximum service temperature of Extruded Graphite EG-HP?
Extruded Graphite EG-HP is rated for continuous use to about 3,000°C (5,432 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Extruded graphite grade data (electrode and general-purpose grades) — SGL Carbon / Mersen / Toyo Tanso (2023)
- Engineered Materials Handbook Vol.4: Ceramics and Glasses — carbon and graphite — ASM International (1991)
- ASTM C709 / C781 — terminology and testing of manufactured carbon and graphite — ASTM (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.