C/C Composite
also Carbon-Carbon
C/C Composite (carbon-carbon) is a carbon-fiber-reinforced carbon-matrix material built from 2D laminates, needled felt, or 3D weaves and densified by CVI or repeated resin/pitch cycles, with SiC-coated variants available.
Reference datasheet — C/C Composite 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.
C/C Composite tempers and conditions
C/C Composite is supplied in 3 conditions, soft to hard.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
needled carbon-felt preform, CVI/impregnation densified | Lowest-cost route for large furnace hardware (crucibles, heaters, guide cylinders) where stiffness matters less than thermal stability. | 90 | 20 W/m·K | |||
mesophase-pitch fiber, high thermal conductivity C/C | Pick for thermal-management / heat-spreader and high-energy brake duty where in-plane conductivity above 200 W/m·K is required. | 150 | 0.15 | 45 HV | 300 W/m·K | |
3D woven / orthogonal preform C/C | Choose when through-thickness strength and delamination resistance are critical (nozzles, throats, brake discs, re-entry structures). | 180 | 50 W/m·K |
Supply forms, finishes and certifications
Ways C/C Composite is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
SIC-COATED | C/C with CVD SiC / Si-based anti-oxidation coating | Supply form |
2DDefault | 2D woven fabric laminate C/C | Surface finish |
What is C/C Composite?
C/C Composite (carbon-carbon) is a carbon-fiber-reinforced carbon-matrix material built from 2D laminates, needled felt, or 3D weaves and densified by CVI or repeated resin/pitch cycles, with SiC-coated variants available. At 1.7 g/cm³ it holds 200 MPa tensile strength and a 60 GPa modulus and stays usable to about 2200 °C in vacuum or inert gas, which is why it replaces monolithic graphite where toughness matters. Uncoated surfaces oxidize in air above roughly 450 °C, machining is slow and diamond-tooled (machinability 35), and cost and lead time are far above molded or isostatic graphite. C/C Composite 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). C/C Composite has a tensile strength of 200 MPa (29 ksi), stronger than 60% of ceramic grades. Elongation at break is 0.4% and the elastic modulus is 60 GPa (8.7 Msi).
What is C/C Composite used for?
- aircraft brake discs
- rocket nozzles
- hot-zone furnace fixtures
- semiconductor susceptors
Advantages
- Ductile — tolerates forming and impact — 0.4%, better than 96% of ceramic grades
- High service temperature — 2,200°C (3,992 °F), better than 96% of ceramic grades
- Lightweight — 1.7 g/cm³ (0.0614 lb/in³), better than 93% of ceramic grades
- Easy to machine — 35/100, better than 85% of ceramic grades
Limitations
- Hard to polish — 20/100, worse than 99% of ceramic grades
- High embodied carbon — 55 kg CO₂/kg, worse than 97% of ceramic grades
- Low stiffness — 60 GPa (8.7 Msi), worse than 83% of ceramic grades
C/C Composite properties
Typical room-temperature values; bars are the position among ceramic grades.
Physical3
C/C Composite 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).
Mechanical9
C/C Composite has a tensile strength of 200 MPa (29 ksi), stronger than 60% of ceramic grades. Elongation at break is 0.4% and the elastic modulus is 60 GPa (8.7 Msi).
Thermal5
C/C Composite is rated for continuous service to 2,200°C (3,992 °F). It conducts heat at 40 W/m·K (23.1 BTU/hr·ft·°F), better than 67% of ceramic grades. Thermal expansion is 1 µm/m·K (0.556 µin/in·°F).
Electrical2
C/C Composite has an electrical resistivity of 2×10⁻⁵ Ω·m.
Chemical & Environmental2
Corrosion resistance is very good (70/100), worse than 59% of ceramic grades.
Sustainability4
Producing a kilogram of C/C Composite takes about 750 MJ of energy and emits 55 kg of CO₂ — more than 96% of ceramic grades. Typical recycled content is 0%.
Manufacturability3
C/C Composite's machinability is fair (35/100, better than 85% 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. C/C Composite is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C/C Composite
Is C/C Composite easy to machine?
Machine dry with diamond/PCD or carbide tooling and strong dust extraction (respirable carbon dust); support laminates to avoid edge delamination and avoid interrupted cuts on coated parts.
Can C/C Composite be welded?
Not weldable — joints are made with carbonizable adhesives/carbon cement, graphite or C/C fasteners, or brazing to metals via SiC-coated interlayers.
Can C/C Composite be formed, bent or molded?
Net-shape is set at the preform stage (fabric layup, needled felt, 3D weaving) then densified by CVI or repeated resin/pitch impregnation-carbonisation cycles and graphitised at 2000–2800 °C; no post-forming is possible.
C/C Composite 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 (impurities)purified grades for semiconductor use <20 ppm ash | 0 – 0.1 | 0.02 |
| Si (coating, SiC-coated variant only)CVD SiC surface layer 50–200 µm, not part of bulk | — | |
| Ccarbon fiber reinforcement + pyrolytic/resin/pitch carbon matrix | ≥ 99 (balance) |
What surface finishes work on C/C Composite?
Purification (halogen gas at high temperature) for semiconductor grades, and CVD SiC / Si-slurry or pyrolytic-carbon sealing coats for oxidation protection above 450 °C; surfaces cannot be plated or painted conventionally.
Equivalent designations
Standards and trade names that resolve to C/C Composite in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Carbon-Carbon
- Also called
- C/C
How much does C/C Composite cost?
C/C Composite is a high-cost ceramic ($$$$), pricier than about 78% 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.
C/C Composite — frequently asked
What is C/C Composite used for?
C/C Composite is typically used for aircraft brake discs, rocket nozzles, hot-zone furnace fixtures and semiconductor susceptors. In short: highest service temperature carbon; tougher than monolithic graphite; strongest carbon material here.
What is the tensile strength of C/C Composite?
C/C Composite has a typical tensile strength of 200 MPa (29 ksi) — stronger than 60% of ceramic grades. Strength varies by condition: see the 3 listed tempers.
Is C/C Composite easy to machine?
Not especially — machinability is rated fair (35/100, better than 85% of ceramic grades). Machine dry with diamond/PCD or carbide tooling and strong dust extraction (respirable carbon dust); support laminates to avoid edge delamination and avoid interrupted cuts on coated parts.
Can C/C Composite be welded?
Not weldable — joints are made with carbonizable adhesives/carbon cement, graphite or C/C fasteners, or brazing to metals via SiC-coated interlayers.
What surface finishes work on C/C Composite?
Purification (halogen gas at high temperature) for semiconductor grades, and CVD SiC / Si-slurry or pyrolytic-carbon sealing coats for oxidation protection above 450 °C; surfaces cannot be plated or painted conventionally.
Can C/C Composite be formed, bent or molded?
Net-shape is set at the preform stage (fabric layup, needled felt, 3D weaving) then densified by CVI or repeated resin/pitch impregnation-carbonisation cycles and graphitised at 2000–2800 °C; no post-forming is possible.
What is the maximum service temperature of C/C Composite?
C/C Composite is rated for continuous use to about 2,200°C (3,992 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does C/C Composite cost?
C/C Composite is a high-cost ceramic ($$$$), pricier than about 78% 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
- ASM Handbook Vol.21: Composites — Carbon-Carbon Composites — ASM International (2001)
- Carbon-Carbon Materials and Composites — Noyes / NASA RP-1254 (Buckley & Edie) (1993)
- SIGRABOND carbon fiber reinforced carbon — SGL Carbon (2022)
- CX/CC series carbon fiber composite for thermal field — Toyo Tanso (2021)
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.