Molded Graphite MG
Grade · default condition
MG = 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.
Values for the MG condition
Other Molded Graphite tempers and conditions
Molded Graphite is listed in 4 conditions; see the grade overview at Molded Graphite.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
MGDefaultThis page 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 MG?
Molded Graphite MG is Molded Graphite in the MG grade — default general-purpose molded block for furnace fixtures, crucibles, casting dies and electrodes where cost matters more than fine detail. Molded Graphite MG 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). Molded Graphite MG 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).
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 MG properties
Typical room-temperature values for Molded Graphite MG; 11 are specific to this condition. Other listed values are Molded Graphite reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical3
Molded Graphite MG 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 MG 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 MG 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 MG 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 MG 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 MG's machinability is excellent (95/100, better than 99% of ceramic grades).
Common Calculations4
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Molded Graphite MG
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.
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.
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) | — |
Molded Graphite MG — frequently asked
What is Molded Graphite MG used for?
Molded Graphite MG 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 MG?
Molded Graphite MG 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 MG 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 MG 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 MG?
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 MG 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 MG?
Molded Graphite MG 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.
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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.