Carbon Carbon Composites

Carbon Carbon Composites

Carbon Carbon CompositesCarbon fibre reinforced carbon composites, also commonly referred to as Carbon Carbon Composites, CFC, CFRC CCM or C/C.  Is an advanced material that is made of carbon fibres and a carbon matrix binder together it creates a composite of highly durable materials for high temperature environments and friction applications.

The basic manufacturing principle of C/C composites involve carbon fibres and a matrix going through several impregnation, pressing and heat treatment cycles. Once these steps are complete, the last step is graphitization between 2000-2400°c. This final process leaves you with a Carbon Carbon Composite material.

Carbon Carbon Composites are the ideal solution for today’s fast moving high temperature environments and heat-treatment industries. Carbon Carbon composites have high mechanical strength, thermal conductivity, prolonged life and are light in weight. This is great solution to many users.  Due to energy savings, increased productivity and an overall reduction in running costs.

Neftec’s Short-Fibre Carbon Carbon Composites

We specialise in Short-Fibre C/C, this is can be known as chopped, random length and or random weave C/C. This type of C/C has many advantages over conventional plain woven Carbon Carbon. The advantages include, excellent machining qualities, higher Inter-laminar strength (greater reduction in de-lamination) and high density.

chopped ccNeftec’s Carbon Carbon Composites it’s usually referred to as a 2.2 or 2.5D Composite, it sits in-between plain woven 2D and 3D composites. In basic terms, it means it offers similar strength advantages of 3D Composites but with comparable cost on par with 2D Composites.

PM Method

We have developed our highly advanced manufacturing process called ‘PM’. The ‘PM Method’ allows us to produce exceptional high-strength composites with shorter production times. The key is to our highly developed Impregnation and heating cycles. Due to these technical advancements we can reduce cycles in this process, while producing even higher quality C/C Composites. This helps us reduce post-production costs, allowing us to pass on these savings to our customers while at the same time helps keep a stable pricing structure. 

The PM Method also helps Neftec reduce their environmental impact due to the reduction in waste material and energy consumption. 

The Importance of Inter-laminar strength over Tensile strength

One of key parts to CFC structural strength is the Inter-laminar Sheer Strength or ILSS for short. ILSS is a measurement of the strength between each laminate.  A lower the ILSS leads to a greater risk of de-lamanition. A leading cause to CFC Composite components failing. Neftec are very keen to highlight of this measurement which is often overlooked. 

There is always an emphasis placed on tensile strength as being a critical property of CFC composite strength. However in most, if not all cases CFC failure it is down to de-lamination due to a low ILSS strength and not because the Tensile strength had been exceeded. Manufacturers really do not highlight the importance of this value and that is why Neftec is keen to educate the importance of ILSS, along with density and flexural strength data.

Key features over other Carbon Carbon Composites

Superior Density. Our Carbon Composite offer exceptional life-spans and superior strength qualities.

PM method, Neftec original technology. Dramatically cuts costs, production and lead times and with an increase in quality and strength.

Neftec uses cut carbon fibre and random layup technique. This gives far greater inter-laminar strength compared to Graphite and Long-fibre. High ILSS decreases fractures and de-lamination.

Compared to other Carbon composites. Neftec’s composites in the same environment can exhibit greater strength over prolonged periods of time. CFC can handle temperatures up to 2400°c

Technical Data

Material Grade

 

PC70

Short/Random Pan Fibre

PC70H

Short/Random Pan Fibre

Bulk Density g/cm3 1.65+ 1.7+
Flexural Strength MPa 200 220
Inter-laminar Shear Strength (ILSS) MPa 18 19+
Compressive Strength MPa 120 200
Young’s Modulus GPa 45 50
Tensile Strength MPa 120 145
( RT-1300C ) 10-6/C 1.1 1.1
Coefficient of Thermal Expansion 10-6/C 10.4 10.4
Thermal Conductivity

(X/Y Axis)

W/m・K 35 35

(Z Axis)

12 12
Specific Heat 20C J/Kg・K 720 TBA
Electrical Resistivity μΩcm 2000 1800
Sharpy Impact Strength KJ/m2 20 20
Shore Hardness   75  75
Temperature Rating    2000°c  2000°c

Material Grade

 

PC30

Short/Random Pan Fibre

PC40

Short/Random Pitch Fibre

Bulk Density g/cm3 1.65 1.65
Flexural Strength MPa 180 180
Inter-laminar Shear Strength (ILSS) MPa 16 16
Compressive Strength MPa 110 190
Young’s Modulus GPa 45 75
Tensile Strength MPa 120 160
( RT-1300C ) 10-6/C 1.1 0.3
Coefficient of Thermal Expansion 10-6/C 10.4 10.6
Thermal Conductivity

(X/Y Axis)

W/m・K 100 130

(Z Axis)

20 29
Specific Heat 20C J/Kg・K 720  740
Electrical Resistivity μΩcm 1400 1200
Charpy Impact Strength KJ/m2  20  20
Temperature Rating  Celcius  2400°c  2400°c

Please note, data is taken from several batches to provide an average value and as such values are not guaranteed.

Carbon/Carbon Composites VS other commonly used High-temperature materials

 

Advantages over Graphite 

  • Higher strength and structural rigidity
  • Higher resistance to fracture
  • CFC structures and fixtures can be made smaller
  • Low Thermal Expansion
Advantages over Ceramic
  • Higher resistance to fracture
  • Higher resistance to thermal shock
  • Can be machined into complex shapes
  • Carbon Composites do not bond
Advantages over Metal
  • Can endure very high temperatures – up to 2500ºC (4500ºF)
  • Lighter in weight – Carbon Composites weigh 1/5th of iron
  • Highly resistant to corrosion and radiation
  • Thermal expansion is far lower in Carbon Composites
Advantages over plastic
  • Can endure very high temperatures – up to 2500ºC (4500ºF)
  • Highly resistant to corrosion and radiation
  • Extremely high wear resistance
  • Thermal expansion is far lower in Carbon Composites