Graphite MLD
Grade
MLD = die/vibration-moulded medium-grain graphite
Cost-effective medium-grain grade for large moulds, casting dies, sintering trays and roughing EDM electrodes.
Values for the MLD condition
Other Graphite tempers and conditions
Graphite is listed in 2 conditions; see the grade overview at Graphite.
- MLD
- PYRO
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
MLDThis page Die/vibration-moulded medium-grain graphite | Cost-effective medium-grain grade for large moulds, casting dies, sintering trays and roughing EDM electrodes. | — | 20 | — | — | 120 W/m·K |
Pyrolytic graphite | Use for thermal-spreader, crucible-liner and thermal-barrier duty where extreme in-plane conductivity plus through-plane insulation and zero permeability are needed. | — | 90 | — | — | 400 W/m·K |
What is Graphite MLD?
Graphite MLD is Graphite in the MLD grade — cost-effective medium-grain grade for large moulds, casting dies, sintering trays and roughing EDM electrodes. Graphite MLD has a tensile strength of 20 MPa (2.9 ksi), weaker than 88% of ceramic grades. The elastic modulus is 10 GPa (1.45 Msi). Graphite MLD has a density of 1.74 g/cm³ (0.0629 lb/in³), lighter than 91% of ceramic grades. It melts at 3,650°C (6,602 °F).
Advantages
- Easy to machine — 94/100, better than 99% of ceramic grades
- Lightweight — 1.74 g/cm³ (0.0629 lb/in³), better than 91% of ceramic grades
- Conducts heat well — 120 W/m·K (69.3 BTU/hr·ft·°F), better than 88% of ceramic grades
Limitations
- Low stiffness — 10 GPa (1.45 Msi), worse than 93% 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 — 420°C (788 °F), worse than 80% of ceramic grades
Graphite MLD properties
Typical room-temperature values for Graphite MLD; 11 are specific to this condition. Other listed values are Graphite reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical3
Graphite MLD has a density of 1.74 g/cm³ (0.0629 lb/in³), lighter than 91% of ceramic grades. It melts at 3,650°C (6,602 °F).
Mechanical10
Graphite MLD has a tensile strength of 20 MPa (2.9 ksi), weaker than 88% of ceramic grades. The elastic modulus is 10 GPa (1.45 Msi).
Thermal5
Graphite MLD is rated for continuous service to 420°C (788 °F). It conducts heat at 120 W/m·K (69.3 BTU/hr·ft·°F), better than 88% of ceramic grades. Thermal expansion is 3.5 µm/m·K (1.94 µin/in·°F).
Electrical2
Graphite MLD has an electrical resistivity of 9.5×10⁻⁶ Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (80/100), better than 56% of ceramic grades.
Sustainability4
Producing a kilogram of Graphite MLD takes about 120 MJ of energy and emits 9 kg of CO₂ — more than 51% of ceramic grades. Typical recycled content is 10%.
Manufacturability3
Graphite MLD's machinability is excellent (94/100, better than 99% of ceramic grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Graphite MLD
Is Graphite easy to machine?
Machines dry and fast with carbide or PCD tooling (no coolant); requires vacuum dust extraction and sharp tools since the dust is abrasive and electrically conductive.
Can Graphite be welded?
Not weldable — parts are joined mechanically (graphite bolts/threads) or with carbon/graphite cement cured and re-baked.
Can Graphite be formed, bent or molded?
Net shape comes from cold isostatic pressing, extrusion or vibration moulding of coke/pitch mix, then baking ~1000 °C, optional pitch re-impregnation and graphitization at 2600–3000 °C; final geometry is achieved by machining, not forming.
What surface finishes work on Graphite?
Common finishes are resin/metal impregnation for imperviousness, halogen purification to <20 ppm ash, and CVD SiC or pyrolytic-carbon coating for oxidation and particle-shedding control; no plating or painting.
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 |
|---|---|---|
| ashresidual Si, Al, Fe, Ca, V oxides; halogen-purified grades <20 ppm | 0 – 0.3 | 0.05 |
| Sfrom petroleum/needle coke feedstock | ≤ 0.05 | 0.02 |
| phenolic resin impregnantonly in impervious (RI) variant | 0 – 15 | 0 |
| Cfixed carbon after graphitization; purified grades reach ≥99.99 % | ≥ 99 (balance) | — |
Graphite MLD — frequently asked
What is Graphite MLD used for?
Graphite MLD is typically used for EDM electrodes, continuous casting molds, crucibles, semiconductor furnace parts and electrodes. In short: fastest-machining ceramic material; self-lubricating high-temperature carbon; standard EDM electrode material.
What is the tensile strength of Graphite MLD?
Graphite MLD has a typical tensile strength of 20 MPa (2.9 ksi) — weaker than 88% of ceramic grades. Strength varies by condition: see the 2 listed tempers.
Is Graphite MLD easy to machine?
Yes — machinability is rated excellent (94/100, better than 99% of ceramic grades). Machines dry and fast with carbide or PCD tooling (no coolant); requires vacuum dust extraction and sharp tools since the dust is abrasive and electrically conductive.
Can Graphite MLD be welded?
Not weldable — parts are joined mechanically (graphite bolts/threads) or with carbon/graphite cement cured and re-baked.
What surface finishes work on Graphite MLD?
Common finishes are resin/metal impregnation for imperviousness, halogen purification to <20 ppm ash, and CVD SiC or pyrolytic-carbon coating for oxidation and particle-shedding control; no plating or painting.
Can Graphite MLD be formed, bent or molded?
Net shape comes from cold isostatic pressing, extrusion or vibration moulding of coke/pitch mix, then baking ~1000 °C, optional pitch re-impregnation and graphitization at 2600–3000 °C; final geometry is achieved by machining, not forming.
What is the maximum service temperature of Graphite MLD?
Graphite MLD is rated for continuous use to about 420°C (788 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM C709 — Standard Terminology Relating to Manufactured Carbon and Graphite — ASTM International (2021)
- ASTM C651 / C695 / C749 / C611 — flexural, compressive, tensile and resistivity test methods for graphite — ASTM International (2020)
- IG-11 / ISO-88 isotropic graphite property sheets — Toyo Tanso (2022)
- EDM-3 / AXF-5Q ultrafine graphite properties — Entegris (POCO Graphite) (2021)
- Specialty graphite grades R6650, R6300, extruded grades — SGL Carbon (2022)
- Impervious graphite (Graphilor) and isostatic grade data — Mersen (2021)
- Engineered Materials Handbook Vol. 4 — Ceramics and Glasses / carbon-graphite properties — ASM International (1991)
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.