Pyrolytic Graphite PG
Grade · default condition
PG = as-deposited pyrolytic graphite
Standard CVD plate/tube stock: impermeable, moderate in-plane conductivity, best strength-to-cost of the PG family.
Values for the PG condition
Other Pyrolytic Graphite tempers and conditions
Pyrolytic Graphite is listed in 5 conditions; see the grade overview at Pyrolytic Graphite.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
mosaic spread 0.8° ± 0.2° | General-purpose HOPG: good crystalline quality for SPM calibration and electrochemistry at moderate cost. | — | 35 | 0.15 | 8 HV | 1,600 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. | — | 40 | — | — | 1,800 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. | — | 50 | 0.2 | 12 HV | 1,200 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. | — | 80 | — | — | 1,500 W/m·K |
PGDefaultThis page As-deposited pyrolytic graphite | Standard CVD plate/tube stock: impermeable, moderate in-plane conductivity, best strength-to-cost of the PG family. | — | 100 | — | — | 300 W/m·K |
What is Pyrolytic Graphite PG?
Pyrolytic Graphite PG is Pyrolytic Graphite in the PG grade — standard CVD plate/tube stock: impermeable, moderate in-plane conductivity, best strength-to-cost of the PG family. Pyrolytic Graphite PG 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). Pyrolytic Graphite PG 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).
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 PG properties
Typical room-temperature values for Pyrolytic Graphite PG; 10 are specific to this condition. Other listed values are Pyrolytic Graphite reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical3
Pyrolytic Graphite PG 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).
Mechanical11
Pyrolytic Graphite PG 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).
Thermal5
Pyrolytic Graphite PG 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).
Electrical2
Pyrolytic Graphite PG has an electrical resistivity of 5×10⁻⁶ Ω·m.
Chemical & Environmental2
Corrosion resistance is excellent (85/100), better than 69% of ceramic grades.
Sustainability3
Producing a kilogram of Pyrolytic Graphite PG takes about 350 MJ of energy and emits 25 kg of CO₂ — more than 81% of ceramic grades. Typical recycled content is 0%.
Manufacturability3
Pyrolytic Graphite PG's machinability is good (55/100, better than 87% of ceramic grades).
Common Calculations4
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Pyrolytic Graphite PG
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.
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.
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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| ashtotal metallic impurities, typically <20 ppm | 0 – 0.01 | 0 |
| CCVD-deposited carbon; HOPG grades typically >99.99 % | ≥ 99.9 (balance) | — |
Pyrolytic Graphite PG — frequently asked
What is Pyrolytic Graphite PG used for?
Pyrolytic Graphite PG 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 PG?
Pyrolytic Graphite PG 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 PG 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 PG 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 PG?
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 PG 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 PG?
Pyrolytic Graphite PG 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
- ASM Engineered Materials Handbook Vol. 4: Ceramics and Glasses — Carbon and Graphite — ASM International (1991)
- Pyroid HT / Pyroid TC pyrolytic graphite property data — Minteq International (Pyrogenics Group) (2020)
- TC1050 Thermal Pyrolytic Graphite (TPG) datasheet — Momentive Technologies (2021)
- HOPG grades ZYA / ZYB / ZYH specification sheet — SPI Supplies / NT-MDT (2022)
- 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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.