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Pyrolytic Graphite

Pyrolytic Graphite is graphite deposited from hydrocarbon gas by CVD, giving a dense 2.2 g/cm³ layered structure that is strongly anisotropic; pressure-annealed APG and HOPG grades (ZYA, ZYB, ZYH) add progressively tighter crystallographic alignment.

High cost $$$$

Reference datasheet — Pyrolytic 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 PG condition

Pyrolytic Graphite tempers and conditions

Pyrolytic Graphite is supplied in 5 conditions, soft to hard. PG is the default FabDigit quotes; the values on this page are for it.

Compare all 5 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
mosaic spread 0.8° ± 0.2°
General-purpose HOPG: good crystalline quality for SPM calibration and electrochemistry at moderate cost.350.158 HV1,600 W/m·K
mosaic spread 0.4° ± 0.1°
Highest-perfection HOPG for X-ray/neutron monochromators and reference-flat AFM/STM substrates; smallest pieces, highest price.401,800 W/m·K
mosaic spread 3.5° ± 1.5°
Economy HOPG grade for routine STM/AFM substrates, electrode blanks and teaching use where mosaic spread is uncritical.500.212 HV1,200 W/m·K
APG / TPG
Pick when maximum in-plane thermal conductivity (>1200 W/m·K) is needed for encapsulated heat spreaders and satellite thermal doublers.801,500 W/m·K
PGDefault
As-deposited pyrolytic graphite
Standard CVD plate/tube stock: impermeable, moderate in-plane conductivity, best strength-to-cost of the PG family.100300 W/m·K

What is Pyrolytic Graphite?

Pyrolytic Graphite is graphite deposited from hydrocarbon gas by CVD, giving a dense 2.2 g/cm³ layered structure that is strongly anisotropic; pressure-annealed APG and HOPG grades (ZYA, ZYB, ZYH) add progressively tighter crystallographic alignment. In-plane thermal conductivity near 300 W/m·K, 100 MPa tensile strength and low outgassing make it the choice for heat spreaders, CVD/MOCVD susceptors and X-ray optics in plate, tube and crucible form. Through-thickness conductivity is a small fraction of the in-plane value, basal planes delaminate under out-of-plane load, air service is limited to about 450 °C, and part size and cost are set by the deposition run. Pyrolytic Graphite has a density of 2.2 g/cm³ (0.0795 lb/in³), lighter than 87% of ceramic grades. It melts at 3,650°C (6,602 °F). Pyrolytic Graphite has a tensile strength of 100 MPa (14.5 ksi), stronger than 50% of ceramic grades. Elongation at break is 0.3% and the elastic modulus is 30 GPa (4.35 Msi).

What is Pyrolytic Graphite used for?

  • heat spreaders
  • susceptors for CVD/MOCVD
  • X-ray monochromators
  • aerospace thermal insulation

Advantages

  • Conducts heat well — 300 W/m·K (173.3 BTU/hr·ft·°F), better than 99% of ceramic grades
  • Ductile — tolerates forming and impact — 0.3%, better than 91% of ceramic grades
  • Lightweight — 2.2 g/cm³ (0.0795 lb/in³), better than 87% of ceramic grades
  • Easy to machine — 55/100, better than 87% of ceramic grades

Limitations

  • Low stiffness — 30 GPa (4.35 Msi), worse than 87% of ceramic grades
  • Low fracture toughness — 1 MPa·√m (0.91 ksi·√in), worse than 84% of ceramic grades
  • High embodied carbon — 25 kg CO₂/kg, worse than 78% of ceramic grades
  • Limited service temperature — 450°C (842 °F), worse than 77% of ceramic grades

Pyrolytic Graphite properties

Typical room-temperature values for Pyrolytic Graphite-PG; bars are the position among ceramic grades.

Physical3

Pyrolytic Graphite has a density of 2.2 g/cm³ (0.0795 lb/in³), lighter than 87% of ceramic grades. It melts at 3,650°C (6,602 °F).

Density2.2 g/cm³0.08 lb/in³
Melting Point (Solidus)3,650°C6,602 °F
Porosity0.5%

Mechanical11

Pyrolytic Graphite has a tensile strength of 100 MPa (14.5 ksi), stronger than 50% of ceramic grades. Elongation at break is 0.3% and the elastic modulus is 30 GPa (4.35 Msi).

Elastic (Young's) Modulus30 GPa4.4 Msi
Shear Modulus4.5 GPa0.65 Msi
Bulk Modulus34 GPa4.9 Msi
Poisson's Ratio0.17
Tensile Strength (Ultimate)100 MPa14.5 ksi
Elongation at Break0.3%
Compressive Strength150 MPa21.8 ksi
Flexural Strength90 MPa13.1 ksi
Shear Strength5 MPa0.73 ksi
Fracture Toughness (K_IC)1 MPa·√m0.91 ksi·√in
Hardness, Mohs1

Thermal5

Pyrolytic Graphite is rated for continuous service to 450°C (842 °F). It conducts heat at 300 W/m·K (173.3 BTU/hr·ft·°F), better than 99% of ceramic grades. Thermal expansion is 1 µm/m·K (0.556 µin/in·°F).

Thermal Conductivity300 W/m·K173 BTU/hr·ft·°F
Specific Heat Capacity710 J/kg·K0.17 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)1 µm/m·K0.56 µin/in·°F
Max Service Temperature (continuous)450°C842 °F
Min Service Temperature-269°C-452 °F

Electrical2

Pyrolytic Graphite has an electrical resistivity of 5×10⁻⁶ Ω·m.

Electrical Resistivity5×10⁻⁶ Ω·m197 µΩ·in
Volume Resistivity5×10⁻⁴ Ω·cm

Chemical & Environmental2

Corrosion resistance is excellent (85/100), better than 69% of ceramic grades.

Corrosion ResistanceExcellent85/100
Chemical Resistance SummaryInert to nearly all acids, alkalis and organic solvents at room temperature; attacked by strong oxidisers (hot HNO3, chromic acid, molten alkali/nitrates), oxidises in air above ~450 °C and reacts with carbide-forming metals (Ti, Zr, Fe) at high temperature.

Sustainability3

Producing a kilogram of Pyrolytic Graphite takes about 350 MJ of energy and emits 25 kg of CO₂ — more than 81% of ceramic grades. Typical recycled content is 0%.

Embodied Energy (primary production)350 MJ/kg150,473 BTU/lb
Embodied Carbon (primary production)25 kg CO₂/kg
Typical Recycled Content0%

Manufacturability3

Pyrolytic Graphite's machinability is good (55/100, better than 87% of ceramic grades).

MachinabilityGood55/100
PolishabilityVery good70/100
Sintering / Firing Temperature2,100°C3,812 °F

Common Calculations4

Specific Strength (UTS / density)calculated45 kN·m/kg
Specific Stiffness (E / density)calculated13.6 MN·m/kg
Thermal Diffusivitycalculated192.1 mm²/s
Thermal Shock Resistance Indexcalculated1,000

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. Pyrolytic Graphite is highlighted; hover a dot for its name, or open the interactive family chart.

501002005001,000234567Density (g/cm³)Yield strength (MPa) — log scale

Working with Pyrolytic Graphite

Is Pyrolytic Graphite easy to machine?

Cuts and grinds easily with carbide/diamond tools dry, but must be supported and fed lightly to avoid basal-plane delamination; EDM and laser cutting also used; capture the conductive dust.

Can Pyrolytic Graphite be welded?

Not weldable — joined by graphite cement, brazing with active (Ti/Cr) filler metals, or mechanical clamping / metal encapsulation for APG heat spreaders.

Can Pyrolytic Graphite be formed, bent or molded?

Net shape is set by CVD onto a mandrel (tubes, crucibles, plates); no plastic forming, and thick deposits must be annealed under pressure to reach APG/HOPG texture.

Pyrolytic 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.

ElementSpec limit (wt %)Nominal
ashtotal metallic impurities, typically <20 ppm0 – 0.010
CCVD-deposited carbon; HOPG grades typically >99.99 %≥ 99.9 (balance)

What surface finishes work on Pyrolytic Graphite?

Basal surfaces are refreshed by adhesive-tape cleaving rather than polishing; CVD SiC/pyrolytic-carbon or metal (Ni, Cu) coatings are applied for oxidation protection and solderability.

Equivalent designations

Standards and trade names that resolve to Pyrolytic Graphite in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

Also called
HOPG

How much does Pyrolytic Graphite cost?

Pyrolytic Graphite 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.

Pyrolytic Graphite — frequently asked

What is Pyrolytic Graphite used for?

Pyrolytic Graphite is typically used for heat spreaders, susceptors for CVD/MOCVD, X-ray monochromators and aerospace thermal insulation. In short: highest in-plane conductivity; densest graphite form; strongly anisotropic properties.

What is the tensile strength of Pyrolytic Graphite?

Pyrolytic Graphite has a typical tensile strength of 100 MPa (14.5 ksi) — stronger than 50% of ceramic grades. Strength varies by condition: see the 5 listed tempers.

Is Pyrolytic Graphite easy to machine?

Reasonably — machinability is rated good (55/100, better than 87% of ceramic grades). Cuts and grinds easily with carbide/diamond tools dry, but must be supported and fed lightly to avoid basal-plane delamination; EDM and laser cutting also used; capture the conductive dust.

Can Pyrolytic Graphite be welded?

Not weldable — joined by graphite cement, brazing with active (Ti/Cr) filler metals, or mechanical clamping / metal encapsulation for APG heat spreaders.

What surface finishes work on Pyrolytic Graphite?

Basal surfaces are refreshed by adhesive-tape cleaving rather than polishing; CVD SiC/pyrolytic-carbon or metal (Ni, Cu) coatings are applied for oxidation protection and solderability.

Can Pyrolytic Graphite be formed, bent or molded?

Net shape is set by CVD onto a mandrel (tubes, crucibles, plates); no plastic forming, and thick deposits must be annealed under pressure to reach APG/HOPG texture.

What is the maximum service temperature of Pyrolytic Graphite?

Pyrolytic 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 Pyrolytic Graphite cost?

Pyrolytic Graphite 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

  1. ASM Engineered Materials Handbook Vol. 4: Ceramics and Glasses — Carbon and Graphite — ASM International (1991)
  2. Pyroid HT / Pyroid TC pyrolytic graphite property data — Minteq International (Pyrogenics Group) (2020)
  3. TC1050 Thermal Pyrolytic Graphite (TPG) datasheet — Momentive Technologies (2021)
  4. HOPG grades ZYA / ZYB / ZYH specification sheet — SPI Supplies / NT-MDT (2022)
  5. Graphite single-crystal and pyrolytic graphite property tables — CRC Handbook of Chemistry and Physics (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.