Selection guide carbon fibre fabric

    Weight Width Weave  Fibre type
    68 g/m2 AERO 100 cm plain Torayca® T300B
    80 g/m2 100 cm plain Tapes from Tenax® UTS50
    80 g/m2 100 cm plain, ± 45 ° Tapes from Tenax® UTS50
    93 g/m2  AERO 100 cm plain Torayca® T300B
    160 g/m2 100 cm plain Tapes from Tenax® UTS50
    160 g/m2 AERO 100 cm plain Tenax® HTA 40
    160 g/m2 100 cm plain HT
    160 g/m2 100 cm plain, spread Pyrofil® TR30S
    160 g/m2 120 cm plain HT
    160 g/m2 AERO 100 cm plain Tenax® HTA 40 or Torayca® T 300
    160 g/m2 AERO 100 cm twill Tenax® HTA 40
    160 g/m2 100 cm twill HT
    160 g/m2 120 cm twill HT
    160 g/m2 AERO 100 cm twill, non-shift Tenax® HTA 40
    200 g/m2 AERO 100 cm plain Tenax® HTA 40 or Torayca® T 300
    200 g/m2 100 cm plain HT
    200 g/m2 120 cm plain HT
    200 g/m2 127 cm plain HT
    200 g/m2 AERO 100 cm twill, non-shift Tenax® HTA 40
    200 g/m2 AERO 100 cm twill Tenax® HTA 40 or Torayca® T 300
    200 g/m2 120 cm twill HT
    245 g/m2 125 cm twill HT
    245 g/m2 AERO 100 cm twill Tenax® HTA 40
    245 g/m2 AERO 100 cm twill, non-shift Tenax® HTA 40
    400 g/m2 125 cm plain HT
    600 g/m2 125 cm twill TORAYCA® T700SC

     

    Carbon fibre

    R&G Kohlefaser

    Further information on R&G eWiki

    Carbon fibres (carbon fibres, carbon fibres) are now produced industrially in large quantities. The demand is currently around 70,000 tonnes and growing dynamically. By 2021, the required quantity is expected to be 116,000 tonnes annually (source AVK).

    Strength classes of carbon fibres:

    Designation

    Tensile strength
    (MPa)

     Tensile modulus
    (GPa)

     Elongatiom at break
    (%)

    HT

    High Tenacity

     3500 - 4500

     230 - 240

     1.8 - 2.0

    IM

    Intermediate Modulus

     4000 - 5500

     280 - 300

     1.8 - 2.0

    HM

    High Modulus

     4000 - 4500

     370 - 430

     1.1 - 1.3

    UHM

    Ultra High Modulus

    2600 - 3800 

     > 600

     0.3 - 0.6


    Comparative strength data

    Carbon fibres are mainly used for the production of carbon fibre reinforced plastic (CFRP). In common usage, terms such as CFRP, carbon, graphite(e), carbon fibre and carbon fibre stand for duromer plastics reinforced with carbon fibre (epoxy resin, polyester resin, vinyl ester resin, phenolic resin).

    The individual carbon fibre has a diameter of about 5-9 micrometres (for comparison, a human hair around 50 micrometres). From these filaments (elementary threads), usually 1,000 to 48,000 filaments are combined into a yarn or roving.

    Rolled onto spools, they are further processed into textile semi-finished products such as woven fabrics, scrims, ribbons, braided tubes, etc.
    With simultaneous impregnation with resins (polyester, vinyl ester, epoxy resin), CFRP profiles and tubes can be manufactured using winding and pultrusion systems.

     

    Carbon fibre yarn construction

    1k = 1000 Filaments per thread

    1k Kohlenstofffaser Carbonfaser Kohlefaser

    3k = 3000 Filaments per thread

    3k Kohlenstofffaser Carbonfaser Kohlefaser

      6k = 6000 Filaments per thread

    6k Kohlenstofffaser Carbonfaser Kohlefaser

    12k = 12000 Filaments per thread

    12k Kohlenstofffaser Carbonfaser Kohlefaser

    24k = 24000 Filaments per thread

    24k Kohlenstofffaser Carbonfaser Kohlefaser

    50k = 50000 Filaments per thread

    50k Kohlenstofffaser Carbonfaser Kohlefaser

     
    The higher the number of filaments per thread, the heavier the fabric. For example, 1k is used for charcoal fabric 93 g/m², 3k for charcoal fabric with 160, 204, 245 g/m² grammage etc..

    Carbon fibre fabrics and carbon fibre non-wovens available from R&G

    R&G Gewebe aus Kohlefaser

    Selection of carbon fabrics and carbon non-wovens

     

    Spread-Tow Carbon fabrics

     

    R&G Spread Tow Kohlefaser Spread Tow fabric enhances the performance of your fibre composite components and provides both weight reduction and surface quality that enables a new, unique design aesthetic. The fabric is drapeable and easy to handle during insertion and cutting.

    Processing information Spread Tow

     

    Hybrid fabrics of carbon / aramid and design fabrics

    R&G Hybridgewebe Kohlefaser AramidfaserMixed-fibre fabrics can complement each other in their properties and are particularly recommended for certain highly stressed and impact-stressed components (e.g. motorbike racing fairings, model ship hulls, surfboards, etc.). A carbon/aramid laminate obtains high stiffness and good compressive strength from the carbon fibre, and increased impact strength from the aramid fibre. Common combinations are carbon/aramid and carbon/glass.

     

    Properties of carbon fibres:

    1. Mechanical and dynamic:

    • High strength
    • High modulus of elasticity
    • Low density
    • Low creep tendency
    • Good vibration damping
    • Low material fatigue

    Strengths exceed those of most metals and other fibre composites. The elongation of CFRP is fully elastic, fatigue resistance and vibration damping are excellent.

    2. Chemical:

    • Chemically inert
    • Non corrosive
    • High resistance to acids, alkalis and organic solvents
    • arbon fibres absorb practically no water

    3. Thermical:

    • Low thermal expansion
    • Low thermal conductivity

    Very low coefficient of thermal expansion, which gives CFRP high dimensional stability.
    Carbon fibres are incombustible. They are stable up to 3000 °C under oxygen exclusion; with oxygen, oxidation takes place from approx. 400 °C, which leads to loss of strength.

    4. Elektromagnetic:

    • Low X-ray absorption
    • Non magnetic

    5. Electric:

    • Good electrical conductivity

    Areas of application for carbon fibres

    • Sports equipment construction (bicycles, model making, fishing rods, rackets of all kinds, skis, surfboards, etc.)
    • Motor sports (Formula 1 monocoques, body parts)
    • Vehicle construction (body parts, chassis, e-mobility)
    • Boat building (masts, hulls)
    • Aircraft construction (complete aircraft structures)
    • Construction (bridges, design elements)
    • Musical instruments (stringed and plucked instruments)

    The processing of carbon fibres

    In order to be able to use the excellent static and dynamic strengths, the fibres are combined into a composite material by embedding them in a resin matrix (usually epoxy resin).
    When processed into laminates, carbon fibres are comparable to textile glass products. Layer by layer, the cut fabric is impregnated with epoxy resin, for example, to produce a laminate.

    Unlike glass fabric, which becomes transparent when properly wetted, carbon fibre remains uniformly black. Air bubbles and unimpregnated areas cannot be detected. Defective spots must be avoided by working carefully with a laminating brush and roller.

    Hand laminate
    The laminating resin should be warmed to room temperature (20 °C) so that it is thin enough to wet the fibres completely. Good wetting, without air pockets, is crucial for the subsequent mechanical properties of the laminate.


    Other processes that offer very high fibre contents and good surfaces for building component laminates are: Vacuum bagging, resin injection, pressing method, autoclave pressing


    CFRP material testing

    Both destructive and non-destructive testing methods are used to test fibre composite structures.

    Destructive testing is used, for example, to test the breaking load of the material or the breaking behaviour.
    Non-destructive testing methods (e.g. ultrasonic or acoustic testing), enable the localisation of defects such as delaminations, blowholes or air bubbles.

    Bonding agent for carbon fibres

    To achieve the best possible adhesion of the resin to the fibre, all R&G carbon fabrics are impregnated with an epoxy-containing preparation. The proportion is 1.3 % of the fabric weight. We recommend epoxy resins as matrix, but processing with polyester resins is also possible.

    Slide bonding of carbon fibre fabrics

    R&G Kohlefaser To prevent the threads from coming loose during cutting, the fabric can be shear-strengthened during production with an additionally applied, resin-friendly binder. The drapeability is retained as far as possible! R&G also supplies various carbon fabrics with this sliding reinforcement as an option. This material offers advantages especially in the production of optical CFRP components and when cutting torsion layers (± 45°). From approx. 100 m², any carbon fabric can be slide-bonded ex works. Due to its binder, the fabric can be thermoplastically formed and bonded with hot air. This process can be reversed at will. Layer alignment in multi-layer constructions takes place without thread displacement. The wettability of epoxy resins as well as the resin flow are not negatively affected. During curing, the EP binder melts and cross-links homogeneously with the matrix above its melting temperature (melting range 103 - 115 °C). If curing takes place below the melting temperature of the binder, it will not cross-link but will also not hinder the fibre-matrix adhesion.

    Instruction for the processing of non-shift carbon fabrics

     

    Special features

    Carbon filament fabrics must never be bent or processed with sharp-edged tools such as metal disc rollers. Damage to the filaments will inevitably result in predetermined breaking points. Folded carbon fabrics should be avoided when purchasing in favour of rolled pieces.

    Storage of carbon fibre fabrics

    According to DIN 65147, carbon fibre fabrics for aerospace applications should be stored horizontally in dry, preferably temperature-controlled rooms, protected from light, so that no external pressure is exerted.

    Carbon fibre safety instructions

    Carbon fibres, fibre fragments and fibre abrasion have some special properties:

    • Exposure to electrical equipment should be avoided due to electrical conductivity.
    • Irritation may occur if the skin is exposed.
    • Wear suitable protective clothing as a precaution
    • Abrasion in the form of respirable dust does not have a fibrous structure and is, therefore, to be classified as inert dust

    Specification of carbon fibre fabrics

    R&G supplies fabrics and rovings mainly made of Tenax® carbon fibres. Most of the wide fabrics are manufactured according to DIN 65 147 T1 and T2 (aviation standard) and the QSF-B guidelines (aviation quality assurance system).