Carbon/graphite felts

Carbon/graphite felts with thicknesses of 6 and 11 mm and a width of 1200 mm are available. Specific widths can be provided and special shapes can be cut to your specifications.

Characteristic properties

  • Low thermal conductivity : Greater than that of loose particle fillings such as granular carbon or metal radiation shields (energy savings of up to 75%).

  • Low specific heat : Allowing for rapid heating and cooling of furnaces

  • High thermal stability : In oxidizing atmospheres up to 350°C, in protective or vacuum atmospheres up to approximately 3000°C for graphite and 1000°C for carbon.

  • Ease of processing : Can be cut with scissors or blades. Flexible – adapted to small flexural radii.

  • Favourable surface properties : Unaffected by nearly all molten metals. Small specific surface area – low adsorption capacity; surface properties may be increased by partial oxidation.

  • High purity : Low sulphur content – no contamination of pump oil in vacuum operation. Low ash content – no smouldering. High-purity grades available for semiconductor applications.

  • No electrostatic charging : When used together with plastics in composite materials.

  • High resistivity : Coupling in an inductive field only occurs above 12 kHz.

Applications

  • Thermal insulation for resistance- or induction-heated vacuum furnaces and inert gas furnaces, such as degassing furnaces, brazing furnaces, soft and bright annealing furnaces, sintering furnaces for hard metals, carburizing furnaces, graphitizing furnaces

  • For inductively heated smelting and holding furnaces, a proportion of the ceramic insulating material is replaced by graphite or soft carbon felt in order to increase the electrical efficiency and to prevent the molten metal from coming into contact with the induction coil in the event of crucible fracture (no wetting of the graphite felt by the molten metals).

  • Filters for hot and/or corrosive gases and liquids, for molten metals (no wetting).

  • Backing strips for soldering and welding - no wetting, no smouldering.

Uses

  • Aerospace
  • Semiconductors and photovoltaic
  • Metallurgy
  • Production of optical fibre
  • Glass and ceramic processing
  • Insulation of induction furnaces

Technical data

 

CARBON FELT

GRAPHITE FELT

TYPICAL PROPERTIES

KFA 5

KFA 10

GFA 5

GFA 10

Weight/Area

g/m²

520-650

1000-1150

470-600

950-1100

Tensile strength

MPa

0.1

0.12

0.1

0.08

 

Resistivity

 

Ohm.cm

0.4-0.6  ǁ

0.35-0.55  ǁ

0.15-0.25  ǁ

0.15-0.25  ǁ

0.7-0.9 ^

0.6-0.8 ^

0.3-0.4 ^

0.3-0.4 ^

Thermal conductivity 

W/m.K

0.25

0.25

0.43

0.43

Specific surface area

m²/g

> 1.5

> 1.5

< 1

< 1

Ash content

%

< 0.3

< 0.3

< 0.05

< 0.05

Sulphur content

%

< 0.03

< 0.03

< 0.001

< 0.001

Sizes

m

25 x 1.2

25 x 1.2

25 x 1.2

25 x 1.2

Thickness

mm

5.5 – 6.5

9.5 – 10.5

5 - 6

9 - 10

The KFA 5, KFA 10 and GFA 5 references are available only in full rolls. GFA 10 is in stock; we offer custom-made cuts according to your needs. GFA 10 can be split into two parts with a thickness of 5mm.

Thread for flexible graphite felt

It is possible to sew or fasten flexible GFA felts together using thread spun using carbon. We stock a reference of thread measuring 2mm in diameter (reference D2-3K).

Properties

 

 

Diameter

mm

2.0

Weight/m

g

1.8

Tensile strength

N

900

Maximum loop resistance

N

600

Maximum knot resistance

N

250

Ash content

%

<0.5

We can also provide 24k and 50k carbon fibres. (References: C T24-4.8/240-E100, C T24-5.0/270-E100, C T50-4.0/240-E100, C T50-4.4/255-E100, C T50-4.0/240-T140)

Carbon Graphite Felts (786.88k)

Technical data sheet: soft carbon graphite felts and rigid graphite felt.


Graphite (1.11M)

Technical data sheet graphite.