Natural Flake Graphite
Natural Flake Graphite is mined crystalline carbon in platelet (flake) form, supplied by fixed-carbon grade from FC94 and FC95-LF through FC99 and high-purity HP-9995, plus expandable EG grades intended for exfoliation.
Reference datasheet — Natural Flake 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 FC94 condition
Natural Flake Graphite tempers and conditions
Natural Flake Graphite is supplied in 4 conditions, soft to hard. FC94 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 |
|---|---|---|---|---|---|---|
FC94Default 94–95 % C, medium/fine flake | Standard flotation-concentrate grade for refractories, foundry coatings, brake pads and pencil/lubricant use — best cost per unit carbon. | 8 | 0.3 | 12 HV | 250 W/m·K | |
99 % C, chemically purified flake | Acid/alkali-leached grade for conductive fillers, carbon brushes, seals and lubricant additives where ash below ~1 % matters. | 8 | 0.4 | 8 HV | 350 W/m·K | |
99.95 % C, high-purity | Ultra-low-ash grade — feedstock for spheroidised Li-ion anode material, nuclear/semiconductor parts and premium expanded-graphite foil. | 8 | 0.5 | 7 HV | 450 W/m·K | |
95 % C, large flake | Coarse, high-aspect-ratio flake commanding a premium — the feedstock for expandable graphite, graphite foil/gaskets and high-end refractories. | 9 | 0.4 | 10 HV | 400 W/m·K |
Supply forms, finishes and certifications
Ways Natural Flake Graphite is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
EG | Expandable graphite | Coating |
What is Natural Flake Graphite?
Natural Flake Graphite is mined crystalline carbon in platelet (flake) form, supplied by fixed-carbon grade from FC94 and FC95-LF through FC99 and high-purity HP-9995, plus expandable EG grades intended for exfoliation. Engineers specify it where in-plane thermal conductivity (about 250 W/m·K), lubricity and electrical conduction matter: lubricant and grease additives, refractory shapes, battery anode feedstock and flexible graphite foil. It ships as sized powder rather than machinable stock, and sustained air service is limited to roughly 450 °C before oxidation dominates. Where purity and conductivity matter less than cost, amorphous graphite is the usual substitute. Natural Flake Graphite has a density of 2.24 g/cm³ (0.0809 lb/in³), lighter than 87% of ceramic grades. It melts at 3,650°C (6,602 °F). Natural Flake Graphite has a tensile strength of 8 MPa (1.16 ksi), weaker than 93% of ceramic grades. Elongation at break is 0.3% and the elastic modulus is 10 GPa (1.45 Msi).
What is Natural Flake Graphite used for?
- lubricant additive
- refractory brick additive
- battery anode feedstock
- foundry facings
Advantages
- Conducts heat well — 250 W/m·K (144.4 BTU/hr·ft·°F), better than 96% of ceramic grades
- Low embodied carbon — 2.5 kg CO₂/kg, better than 92% of ceramic grades
- Ductile — tolerates forming and impact — 0.3%, better than 91% of ceramic grades
- Easy to machine — 85/100, better than 91% of ceramic grades
- Lightweight — 2.24 g/cm³ (0.0809 lb/in³), better than 87% of ceramic grades
Limitations
- Low fracture toughness — 0.8 MPa·√m (0.728 ksi·√in), worse than 99% of ceramic grades
- Low stiffness — 10 GPa (1.45 Msi), worse than 93% of ceramic grades
- Limited service temperature — 450°C (842 °F), worse than 77% of ceramic grades
Natural Flake Graphite properties
Typical room-temperature values for Natural Flake Graphite-FC94; bars are the position among ceramic grades.
Physical2
Natural Flake Graphite has a density of 2.24 g/cm³ (0.0809 lb/in³), lighter than 87% of ceramic grades. It melts at 3,650°C (6,602 °F).
Mechanical12
Natural Flake Graphite has a tensile strength of 8 MPa (1.16 ksi), weaker than 93% of ceramic grades. Elongation at break is 0.3% and the elastic modulus is 10 GPa (1.45 Msi).
Thermal5
Natural Flake Graphite is rated for continuous service to 450°C (842 °F). It conducts heat at 250 W/m·K (144.4 BTU/hr·ft·°F), better than 96% of ceramic grades. Thermal expansion is 1 µm/m·K (0.556 µin/in·°F).
Electrical2
Natural Flake Graphite has an electrical resistivity of 7×10⁻⁶ Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (82/100), better than 61% of ceramic grades.
Sustainability4
Producing a kilogram of Natural Flake Graphite takes about 30 MJ of energy and emits 2.5 kg of CO₂ — less than 94% of ceramic grades. Typical recycled content is 0%.
Manufacturability1
Natural Flake Graphite's machinability is excellent (85/100, better than 91% 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. Natural Flake Graphite is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Natural Flake Graphite
Is Natural Flake Graphite easy to machine?
Supplied as powder — not machined; processing is milling, air classification, spheroidisation and screening, with dust control (combustible dust, low ignition energy) and no lubricants that contaminate ash.
Can Natural Flake Graphite be welded?
Not weldable; joining of graphite bodies made from this powder relies on carbonaceous cements, resin/pitch binders or mechanical clamping.
Can Natural Flake Graphite be formed, bent or molded?
Blended with pitch, resin, clay or metal binders and pressed/extruded/isostatically compacted; intercalated flake is exfoliated then roll-formed into flexible graphite foil without any binder.
Natural Flake 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 |
|---|---|---|
| Cfixed carbon on dry basis, GB/T 3521 method | 94 – 95 | 94.5 |
| moistureas-shipped | 0 – 0.5 | 0.3 |
| volatile matter | 0 – 1.2 | 0.8 |
| Shigher in acid-treated/expandable grades | 0 – 0.15 | 0.05 |
| Fepart of ash; <50 ppm in HP-9995 | 0 – 1 | 0.4 |
| ash (SiO2+Al2O3+Fe2O3+CaO)silicate gangue from ore | ≥ 4 (balance) |
What surface finishes work on Natural Flake Graphite?
Formed parts can be impregnated with resin or phosphate/CVD SiC coatings for oxidation protection; loose powder is dedusted, coated (pitch/carbon-coated for anodes) or surface-treated for wetting in polymer compounds.
Equivalent designations
Standards and trade names that resolve to Natural Flake Graphite in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Also called
- Flake Graphite
How much does Natural Flake Graphite cost?
Natural Flake Graphite is a budget-cost ceramic ($), cheaper than about 90% 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.
Natural Flake Graphite — frequently asked
What is Natural Flake Graphite used for?
Natural Flake Graphite is typically used for lubricant additive, refractory brick additive, battery anode feedstock and foundry facings. In short: highest-conductivity natural graphite; feedstock for flexible foil; powder form, not stock shapes.
What is the tensile strength of Natural Flake Graphite?
Natural Flake Graphite has a typical tensile strength of 8 MPa (1.16 ksi) — weaker than 93% of ceramic grades. Strength varies by condition: see the 4 listed tempers.
Is Natural Flake Graphite easy to machine?
Yes — machinability is rated excellent (85/100, better than 91% of ceramic grades). Supplied as powder — not machined; processing is milling, air classification, spheroidisation and screening, with dust control (combustible dust, low ignition energy) and no lubricants that contaminate ash.
Can Natural Flake Graphite be welded?
Not weldable; joining of graphite bodies made from this powder relies on carbonaceous cements, resin/pitch binders or mechanical clamping.
What surface finishes work on Natural Flake Graphite?
Formed parts can be impregnated with resin or phosphate/CVD SiC coatings for oxidation protection; loose powder is dedusted, coated (pitch/carbon-coated for anodes) or surface-treated for wetting in polymer compounds.
Can Natural Flake Graphite be formed, bent or molded?
Blended with pitch, resin, clay or metal binders and pressed/extruded/isostatically compacted; intercalated flake is exfoliated then roll-formed into flexible graphite foil without any binder.
What is the maximum service temperature of Natural Flake Graphite?
Natural Flake 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 Natural Flake Graphite cost?
Natural Flake Graphite is a budget-cost ceramic ($), cheaper than about 90% 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
- GB/T 3518 (Flake graphite) (2008)
- GB/T 3521 (Chemical analysis of graphite) — SAC (2008)
- ASTM C561 Standard Test Method for Ash in a Graphite Sample — ASTM International (2019)
- ASM Engineered Materials Handbook, Vol. 4 — Ceramics and Glasses (carbon/graphite section) — ASM International (1991)
- CRC Handbook of Chemistry and Physics — properties of carbon (graphite) — CRC Press (2020)
- USGS Mineral Commodity Summaries — Graphite (natural) — U.S. Geological Survey (2024)
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.