Rigid Boards

Graphite Insulation Boards Foil

What are Carbon & Graphite Boards?

Rigid boards are made of rigidized Pan long fiber felt or Rayon Sliced foam and are used as insulation for vacuum or protective atmosphere process furnaces. Both the Graphite and Carbon boards are easily cut or machined to custom sizes and can be used in both square and round hot zones. Our office recommends rigidized felt for heat treating vacuum furnaces and hot pressing due to the materials courses fiber, oxidation resistance, lower price point, and the same great performance.

Additionally, our office offers foil layered graphite insulation boards that are manufactured with alternating layers of rigidized felt and graphite foil with foil on both sides of the board. This creates a very stiff and dimensionally stable strong material that provides excellent erosion resistance, thermal uniformity, and great machining capabilities. These boards can be produced up to 10″ thick x 60″ x 60″ and fabricated into large cylinders. Manufactured to order but our office does stock 1″ x 40″ x 60″ boards.


  • The boards can be made in complex shapes and made to print in large sizes. Please contact us for a custom quote.
  • Surfaces and edges can be sealed using our GraphiSeal to reduce porosity and improve oxidation resistance.
  • Graphite & Carbon Boards can have foil added to the surface(s) or layered internally to increase radiant heat retention significantly while reducing issues with furnace contaminant containment.
  • Added foil aids in decreasing pump down times and increasing the longevity of the insulation.
  • Similarly, CFC covering on the boards provide durability, impact and wear resistance.
Graphite Insulation Board Carbon Board


  • Vacuum Furnaces
  • Powdered Metal Sintering
  • Annealing & Hot Pressing
  • Silicon / GaAs Crystal Growing Furnaces
  • Sputtering Targets
  • Fiber Optics Production.
  • CVD, CVI, and CVR Furnaces
  • Graphite Purification Furnaces
  • Carbon Fiber Heat Treating Furnaces

Useful Charts

Carbon Board Properties
PropertiesUnitCarbon Boards
Carbon Content%≥ 95
Specific ResistanceOhm.cm0.18 - 0.22
Ash Contentppm≤ 500
Ash Content Purifiedppm≤ 10
Temperature Rating1℉ | ℃5432 | 3000
Thermal ConductivityW/mk0.15-0.25
Pre-fire Temperature℉ | ℃2192 | 1200
Standard Size Boardinches40" x 60"
Max Size Boardinches60" x 60"
Max Board Thicknessinches≥ 20"
Alternate Sizing & PuritiesStandard | MetricContact Us
Notes:1Temperature rating in vacuum or inert atmosphere
Graphite Board Properties
PropertiesUnitGraphite Boards
Carbon Content%≥ 98-99.9
Thermal Conductivity
3632℉ | 2000℃
4532℉ | 2500℃
Specific Resistanceohm.cm0.18 - 0.22
Bending StrengthMPa1.10
Compressive StrengthMPa1
Ash Contentppm≤ 1000
Ash Content Purifiedppm≤ 20
Moisture Absorption%≤ 1.0
Temperature Rating1℉ | ℃5432 | 3000
Pre-fire Temperature℉ | ℃3992 | 2200
Standard Size Boardinches40" x 60"
Max Size Boardinches60" x 60"
Max Board Thicknessinches≥ 20"
Alternate Sizing & PuritiesStandard | MetricContact Us
Notes:1Temperature rating in vacuum or inert atmosphere
Rigid Board Info & Pricing
Process Temp.
(g/cm³ | lb/ft³)
Weight per Board
Foil Coating
(Rigidized PAN Felt)
12001" x 40" x 60"0.2515.6122$850.00$1050.00
(2 Sides)
12001.5" 40" x 60"0.2515.6132$1,100.00$1,300.00
(2 Sides)
12002" x 40" x 60"0.2515.6143$2,200.00$2,400.00
(2 Sides)
12004" x 40" x 60"0.2515.6186$2,600.00$2,750.00
(2 Sides)
(Rayon Sliced Foam)
20001" x 24" x 52"0.2414.9811$565.00$615.00
20001" x 40" x 60"0.2414.9821$1,100.00$1,150.00
20001.5" x 24" x 52"0.2414.9816$850.00$900.00
20001.5" 40" x 60"0.2414.9831$1,650.00$1,750.00
20002" x 24" x 52"0.2414.9822$1,125.00$1,175.00
20002" x 40" x 60"0.2414.9841$2,160.00$2,210.00
20004" x 24" x 52"0.2414.9843$2,630.00$2,680.00
20004" x 40" x 60"0.2414.9883$4,350.00$4,400.00
Need a custom size? Contact us for a quote.

Ready to order Graphite & Carbon Boards?

  • Carbon boards are stocked in 60 inch x 40 inch x all thicknesses above with foil on 2 sides for same day shipping.
  • Graphite boards 60 x 40 inch & 52 x 24 with foil on 1 side ship within 1 week.
  • The Boards can be covered on one or both surfaces with the following
    • Graphite foil (0.015″ thick) = $50 per side.
    • Carbon-fiber-composite (0.030″ thick) = ~$250-$450 per side.
  • Board thickness capability up to 20 inches thick.
  • Custom high temperature heat treatment up to 2600°C & halogen purification available.

If you have any additional questions or need a custom quote, our team is always available to help.