Molded Graphite
Molded Graphite is a synthetic carbon produced by vibration molding of carbon paste, then baking, optional impregnation and graphitization, giving a grain size and price between extruded and isostatic grades (MG, MG-FG, MG-HD, MG-P).
Reference datasheet — Molded Graphite is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the MG condition
Molded Graphite tempers and conditions
Molded Graphite is supplied in 4 conditions, soft to hard. MG is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
MGDefault Medium-grain vibration-molded graphite | Default general-purpose molded block for furnace fixtures, crucibles, casting dies and electrodes where cost matters more than fine detail. | 15 | 115 W/m·K | |||
Halogen-purified molded graphite | Use for semiconductor, PV, single-crystal growth and metallurgical melting where contamination from ash and metals is unacceptable. | 19 | 0.2 | 40 HV | 115 W/m·K | |
Fine-grain molded graphite | Pick when fine detail, sharp edges, tighter tolerances or higher strength are needed — EDM electrodes, molds, sealing rings. | 24 | 100 W/m·K | |||
High-density pitch/resin re-impregnated molded graphite | Choose for gas/liquid-tight duty and higher strength — heat-exchanger blocks, pump parts, vacuum furnace hot-zone hardware. | 28 | 120 W/m·K |
What is Molded Graphite?
Molded Graphite is a synthetic carbon produced by vibration molding of carbon paste, then baking, optional impregnation and graphitization, giving a grain size and price between extruded and isostatic grades (MG, MG-FG, MG-HD, MG-P). Engineers specify it for 115 W/m·K thermal conductivity, very easy dry machining (machinability 95) and low cost in large blocks, plates and rods. Tensile strength is only 15 MPa with a 9 GPa modulus, so it is brittle and notch-sensitive, and air service is limited to about 450 °C by oxidation. Where finer grain and closer isotropy are required, isostatic graphite is the nearest alternative. Molded Graphite has a density of 1.72 g/cm³ (0.0621 lb/in³), lighter than 92% of ceramic grades. It melts at 3,650°C (6,602 °F). Molded Graphite has a tensile strength of 15 MPa (2.18 ksi), weaker than 90% of ceramic grades. The elastic modulus is 9 GPa (1.31 Msi).
What is Molded Graphite used for?
- crucibles
- molds
- electrodes
- structural carbon parts
Advantages
- Easy to machine — 95/100, better than 99% of ceramic grades
- Lightweight — 1.72 g/cm³ (0.0621 lb/in³), better than 92% of ceramic grades
- Conducts heat well — 115 W/m·K (66.4 BTU/hr·ft·°F), better than 87% of ceramic grades
Limitations
- Low stiffness — 9 GPa (1.31 Msi), worse than 95% of ceramic grades
- Hard to polish — 35/100, worse than 93% of ceramic grades
- Low fracture toughness — 1 MPa·√m (0.91 ksi·√in), worse than 84% of ceramic grades
- Limited service temperature — 450°C (842 °F), worse than 77% of ceramic grades
Molded Graphite properties
Typical room-temperature values for Molded Graphite-MG; bars are the position among ceramic grades.
Physical3
Molded Graphite has a density of 1.72 g/cm³ (0.0621 lb/in³), lighter than 92% of ceramic grades. It melts at 3,650°C (6,602 °F).
Mechanical10
Molded Graphite has a tensile strength of 15 MPa (2.18 ksi), weaker than 90% of ceramic grades. The elastic modulus is 9 GPa (1.31 Msi).
Thermal5
Molded Graphite is rated for continuous service to 450°C (842 °F). It conducts heat at 115 W/m·K (66.4 BTU/hr·ft·°F), better than 87% of ceramic grades. Thermal expansion is 3.2 µm/m·K (1.78 µin/in·°F).
Electrical2
Molded Graphite has an electrical resistivity of 9.5×10⁻⁶ Ω·m.
Chemical & Environmental2
Corrosion resistance is excellent (85/100), better than 69% of ceramic grades.
Sustainability4
Producing a kilogram of Molded Graphite takes about 130 MJ of energy and emits 9 kg of CO₂ — more than 55% of ceramic grades. Typical recycled content is 5%.
Manufacturability3
Molded Graphite's machinability is excellent (95/100, better than 99% of ceramic grades).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the ceramic family
Yield strength against density for every ceramic grade FabDigit runs. Molded Graphite is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Molded Graphite
Is Molded Graphite easy to machine?
Machines dry and very fast with carbide or PCD tooling — no coolant, but sealed dust extraction and edge-chipping precautions are mandatory.
Can Molded Graphite be welded?
Cannot be welded; sections are joined with carbon/graphite cements, resin adhesives or mechanical graphite fasteners.
Can Molded Graphite be formed, bent or molded?
Net shape comes from vibration molding of the green paste followed by baking, optional impregnation and graphitization; final geometry is achieved by machining, not forming.
Molded 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≤20 ppm (0.002 %) for halogen-purified MG-P grade | 0 – 0.5 | 0.2 |
| Sresidual from coke | ≤ 0.05 | 0.02 |
| Cgraphitized petroleum coke aggregate + coal-tar pitch binder coke | ≥ 99 (balance) |
What surface finishes work on Molded Graphite?
Can be pitch/resin or CVD-SiC/pyrocarbon coated, halogen-purified, or simply deburred and vacuum-cleaned; painting and plating are not used.
How much does Molded Graphite cost?
Molded Graphite is a premium-cost ceramic ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Molded Graphite — frequently asked
What is Molded Graphite used for?
Molded Graphite is typically used for crucibles, molds, electrodes and structural carbon parts. In short: mid-grain, mid-cost graphite; fastest dry machining; cheaper than isostatic grades.
What is the tensile strength of Molded Graphite?
Molded Graphite has a typical tensile strength of 15 MPa (2.18 ksi) — weaker than 90% of ceramic grades. Strength varies by condition: see the 4 listed tempers.
Is Molded Graphite easy to machine?
Yes — machinability is rated excellent (95/100, better than 99% of ceramic grades). Machines dry and very fast with carbide or PCD tooling — no coolant, but sealed dust extraction and edge-chipping precautions are mandatory.
Can Molded Graphite be welded?
Cannot be welded; sections are joined with carbon/graphite cements, resin adhesives or mechanical graphite fasteners.
What surface finishes work on Molded Graphite?
Can be pitch/resin or CVD-SiC/pyrocarbon coated, halogen-purified, or simply deburred and vacuum-cleaned; painting and plating are not used.
Can Molded Graphite be formed, bent or molded?
Net shape comes from vibration molding of the green paste followed by baking, optional impregnation and graphitization; final geometry is achieved by machining, not forming.
What is the maximum service temperature of Molded Graphite?
Molded Graphite is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Molded Graphite cost?
Molded Graphite is a premium-cost ceramic ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM C709 / C651 / C695 — Standard test methods for manufactured carbon and graphite — ASTM (2021)
- ASM Engineered Materials Handbook Vol. 4 — Ceramics and Glasses (carbon/graphite section) — ASM International (1991)
- Molded and extruded fine-grain graphite grade datasheets — SGL Carbon / Toyo Tanso / (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.