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Fibre Chemistry, Vol. 42, No. 5, March, 2011 (Russian Original No. 5, September-October, 2010)

WORLD PRODUCTION AND CONSUMPTION OF CARBON FIBRES

M. T. Azarova and M. E. Kazakov

The total world production volume of carbon fibres (CF) is 70-80,000 tons/year. In the last two to threeyears, there has been a trend toward significant growth in their production and use. Polyacrylonitrile fibreis the basic type of raw material for production of CF. New areas of application of CF have appeared. Thequality level attained for carbon fibres is examined on the example of several leading manufacturers.

Carbon fibres are third-generation materials. Having a set of valuable properties such as high mechanical indexes(strength and modulus of elasticity), low density, electrical and thermal conductivity, almost absolute chemical inertness,and thermal stability and heat resistance, these materials allowed solving a number of complex problems in different sectorsof engineering, and aircraft and rocket construction. With respect to the specific mechanical characteristics (ratio of strengthand modulus of elasticity to density), high-strength and high-modulus carbon fibres and the carbon-fibre-reinforced plasticsmade from them are 5-8 times superior to their metal analogs (steel, aluminum, and alloys), so that using them allowsreducing the weight of articles while simultaneously increasing the elastic and strength properties.

RAW MATERIALS FOR PRODUCTION OF CARBON FIBRESAND TOTAL PRODUCTION VOLUME

Although the first samples of carbon fibres (CF) were obtained previously, systematic studies were actively begunin the 1970s after the English scientists Watt and Johnson announced the creation of a process for production of continuouscarbon fibres from polyacrylonitrile [1]. The 1970s-80s were marked by active research in this direction not only in Europe,but also to a greater degree in Japan and the USA, and in the ‘80s, the first CF production plants were created. The researchincluded a search for sources of raw materials, construction of equipment, and simultaneous improvement of fibre qualityindexes. Despite the fact that different types of fibre materials were used for manufacturing CF, polyacrylonitrile (PAN),hydrated cellulose (HC) fibres and residual products from refining oil and coal (pitch) remain the basic raw material sources.This drew the attention of scientists, since they were creating finished polycyclic structures from which graphite-like layersof the final material are easily formed. When pitches are used, the raw material flow factor was very advantageous: 1 kg ofcarbon fibre can be obtained from 2 kg pitch (2:1), while this ratio is 3:1 for PAN fibre and 8:1 for HC.

In addition to the advantages, pitch raw material had important drawbacks, in particular, carcinogenicity and complextreatment of the pitches to ensure their suitability for spinning fibres. For these reasons, especially the first one, the researchin this direction was phased out in many countries, including in Russia.

Three companies in the world are working with this technology – Kureha (Japan), Cytec and Conoco (USA). Inrecent years, there has been almost no information on Kureha’s activity, except that it may have stopped manufacturing pitchmaterials. The American companies modified the pitch raw material, creating a mesophase in it, so that CF with satisfactorystrength indexes and a very high modulus of elasticity were obtained. The last index advantageously distinguishes this classof materials from the analogs. Moreover, due to the large diameter of the elementary fibre, it is very brittle.

UVIKOM Science and Production Center, Mytishchi. Translated from Khimicheskie Volokna, No. 5, pp. 4-9,September-October, 2010.

_________________________UVIKOM Science and Production Center: 141009, Mytishchi, ul. Kolontsova, 5.

0015-0541/11/4205-0271 © 2011 Springer Science+Business Media, Inc.

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Pitch fibres are spun from melt. This technology is relatively complex, so that exclusively type 2K and 4K thinfibres containing 2000 and 4000 elementary fibres of large diameter (10-11 ì m) are manufactured..

A few companies are working on manufacturing CF from HC raw material. This basically concerns small productionvolumes for internal consumption. The main area of application is military engineering, which is the cause of the shortageof information to a significant degree.

CF are not currently being manufactured from hydrated cellulose in Russia, but there is scientific and technicalcooperation between Russian researchers from UVIKOM Scientific and Production Center and the Belorussian KhimvoloknoSPA (Svetlogorsk), which was created based on Russian developments.

The drawbacks of hydrated cellulose CF include the average level of the mechanical indexes and the high rawmaterial consumption. Moreover, even after graphitization, the fibres remain soft and elastic, which makes them suitable fortextile processing into a different type of structure. In addition to materiel, fabrication of chemically inert gasket packingused in aggressive media even at high temperatures and heating elements and medical goods are the preferred areas ofapplication of graphitized HC.

Fig. 1. Carbon Fibre Production by Leading Manufacturers: 1 – «Zoltek»; 2 – «Toray»;3 – «Toho»; 4 – «Mitsubishi»; 5 – «Hexcel»; 6 – «Cytec»; 7 – SCL; 8 – «Other».

TABLE 1. Expansion of Toray Co. Production

Manufacturing country

Output, tons

2005 January 2006 January 2006 August 2007

Japan France USA

4700 2600 1800

4700 2600 3600

6900 2600 3600

6900 3400 3600

Total 9100 1090 13100 13900

TABLE 2. Properties of Cytec Carbon Fibres from Mesophase Pitches

Indexes Fib re brand

P-25 P-5 5S P-100S P-120S K-800X K-1100

Strength, GPa 1.4 1.9 2.4 2.4 2.34 3.1

Modulus of elasticity, GPa 160 380 760 827 896 965

Density, g/cm3 1.9 2.0 2.16 2.17 2.20 2.20

Elongation, % 0.9 0.5 0.3 0.3 0.3 -

Filament diameter, μm 11 10 10 10 10 10

Carbon content, % 97 99 99 99 99 99

72000

63000

54000

45000

36000

27000

18000

9000

0O

utpu

t, to

ns

1

2

3

4

5678

2004 2005 2006 2007 2008 2009 2010Year

273

The production volume of hydrated cellulose carbon fibres has not been reported, but most of the CF in the worldare made from PAN fibres. The highest quality CF which combine high strength with a high modulus of elasticity are madefrom this type of initial raw material.

The evolution of carbon fibres has not been smooth. The euphoria of the 1970s was replaced by a long period ofstagnation when production capacities were moribund until 2000-2001 due to the high cost of CF in comparison to metalanalogs or glass fibre. In this period, aviation and space engineering and sporting goods were the basic areas of applicationof carbon fibres. Their use in civil aviation and in new energy sources (wind turbine blades) stimulated the wide use ofCF-based composites (carbon-fibre-filled plastics). Work began on the use of parts made of carbon-fibre-filled plastics intwo passenger aircraft – the US Boeing 787 and the European A380 – at the beginning of the 21st century [2]. Theseprograms ended in 2005-2006: the first airplanes with parts made of composites passed the tests and contracts were signedto manufacture them for 15 years. At this time, most of the leading firms that manufacture CF were expanding their plants[3]. In 2005, the Japanese company Toray revealed a significant increase in production volumes in all of its plants, both inJapan and in Europe and the USA. The reorganization included creating larger production lines and increasing the rawmaterial production volume (Table 1).

The large American company Zoltek announced doubling of production of different types of CF. Cytec (USA) isplanning to invest an additional $150 million to expand production of its products. This also totally relates to the othermanufacturers, which is illustrated by the diagram in Fig. 1.

TABLE 3. Properties of Toray Carbon Fibres

Fibre type Number of filaments Strength, GPa Modulus of elasticity, GPa Elongation, % Linear density, tex Density, g/cm3

T 300

1.000 3.000* 6.000* 12.000

3.53 230 1.5

66 198 396 800

1.76

T 300J 3.000* 6.000* 12.000

4.21 230 1.8 198 396 800

1.78

T400 3.000 6.000

4.41 250 1.8 198 396

1.80

T600S 24.000** 4.12 230 1.9 1.700 1.79

T700S 6.000

12.000** 24.000**

4.9 230 2.1 400 800

1.650 1.80

T700G |12.000** 24.000**

4.9 240 2.0 800 1650

1.78

T800? 6.000*

12.000* 5.49 240 1.9 223 445

1.81

T1000G 12.000 6.37 294 2.2 485 1.80

M35J 6.000 12.000

4.7 343 1.4 225 450

1.75

M40J 6.000* 12.000*

4.41 377 1.2 225 450

1.77

M46J 6.000* 12.000*

4.21 436 1.0 223 445

1.84

M50J 6.000 4.12 475 0.8 216 1.88 M55J 6.000 4.0 540 0.8 218 1.91

M60J 3.000 6.0000

3.9 588 0.7 100 200

1.94

M30S 18.000** 5.49 294 1.9 760 1.73

M40

1.000 3.000 6.000

12.000*

2.74 392 0.7

61 182 364 728

1.81

______________ *Manufactured in France. **Manufactured in the USA.

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CHARACTERISTICS OF CARBON FIBRES

The level of the properties of carbon fibres attained can be assessed on the example of the products of severalleading world manufacturers.

The properties of CF made from Cytec mesophase pitches are shown in Table 2. As noted above, mesophase pitchcan be used as raw material to manufacture CF with a very high modulus of elasticity. The optimum area of use is formanufacturing items for which the rigidity index is determining, for example, tubes for solar batteries or parts for ultrasonicaircraft. Conoco CF have approximately the same indexes. Kureha spins fibres from isotropic pitch with strength of 1.5-2.0GPa and modulus of elasticity of 200-230 GPa.

The basic manufacturers of high-quality carbon fibres use PAN fibre as the raw material, and each firm usually usesits own raw material.

Toray is the leading firm in the world both in production volumes and in the quality of the CF. It created a fibre witha maximum strength of 6.37 GPa (Table 3, T1000G), but due to the superhigh cost, it has almost not been mass produced.The production technology has not been divulged. T300 (strength of 3.53 GPa, modulus of elasticity of 230 GPa), and T700fibres (strength of 4.9 GPa, modulus of elasticity of 235-245 GPa) are the most common. The company simultaneouslycreated an entire line of high-modulus materials (M35J-M60J) with a maximum modulus of elasticity of 588 GPa.

Toray’s basic assortment consists of untwisted complex fibres containing 1000, 3000, 6000, and 12,000 filaments(types 1K, 3K, 6K, and 12 K).

TABLE 4. Properties of Zoltec Carbon Fibres

Index Fibre

«Panex-33-0048» «Panex-33 -0160» «Panex-33 -0320»

Strength, GPa 3.79 3.67 3.67

Modulus of elasticity, GPa 230 228 228

Elongat ion, % 1.5 1.5 1.5

Density, g/cm3 1.8 1.8 1.8

Nu mber of fi laments 48000 160000 320000

Filament diameter, μm 7 7 7

Linear density, tex 3500 12200 24400

TABLE 5. Properties of Toho Rayon Carbon Fibres

Index Fibre

HTA 5131 HTS 5631 IMS 3131 IMS 5131 UTS 5631

Linear density, tex 200, 400 800, 1600 680 410 800

Filament diameter, μm 7 7 6.4 5 7

Number of fi laments 3000, 6000 12000, 24000 12000 12000, 24000 12000

Strength, GPa 3.95 4.3 4.12 5.6 4.8

Modulus of elast icity, GPa 23.8 23.8 29.5 29.0 24.0

Elongat ion, % 1.7 1.8 1.4 1.9 2.0

Density, g/cm3 1.76 1.76 1.76 1.8 1.79

Twist, tw./m O/Z 10-15 0 0 0 0

Finish content, % 1.3* 1** 1.3* 1.3* 1** ______________ *Epoxy resin. **Polyurethane

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Zoltek, which has two large factories in the US and Hungary, in an attempt to manufacture cheaper materials, wentfrom manufacturing thin nominals and switched to production of 48K, 160K, and 320K CF containing 48,000, 160,000, and320,000 filaments. All of this company’s materials are manufactured under the trade mark PANTEX® 33; their propertiesare reported in Table 4.

Toho Rayon, which is third in the world in production volume, is manufacturing fibres both in Japan and in Europe.In particular, the firm created Tenax Fibers GmbH Co. in Germany together with Akzo Nobel Faser AG. The quality indexesof the fibres manufactured by Toho Rayon are reported in Table 5.

The analysis of the indexes for carbon fillers from the three leading manufacturers gives an idea of the level of theproperties of the CF attained. The most mass-produced materials have strength of 3.5-4.5 GPa, which is totally sufficient formost items. The Japanese T300 fibre is widely used in many structures, although it has recently been replaced by the T700fibre.

UKN, an analog of T300, which is manufactured on the industrial scale, has been developed in Russia. The propertiesof the Russian fibres, fabrics, and ribbon are reported in Table 6.

ASSORTMENT OF CARBON MATERIALS

Continuous carbon fibres containing a different number of elementary fibres – from 1000 to 320,000 – are the basictype of carbon materials. The thinnest nominals, 1K and 3K, are usually processed into fabrics and ribbon convenient forfabrication of articles by laying out. Some companies, Zoltek, for example, manufacture the fabrics themselves, whileothers, such as Toray and Toho, prefer to manufacture complex fibres alone. Companies specializing in manufacture offabric items of different types from carbon fibres have arisen in recent years. Porcher Ltd. in France, Saertex in Germany,and Taiwan Electric Insulator Co. have become widely known. They not only manufacture purely carbon but also combinedfabrics containing aramid or glass fibres in addition to carbon fibres. Zoltek and Toho also manufacture cut fibres with agiven cut length for filling plastics to remove static electricity. Barthels”Feldhoff Co. (Germany) weaves hollow cylindricalcord up to 200 mm in diameter both from purely carbon fibres and by combining them with organic and glass fibres.

Due to the creation of carbon twists of large nominals 24K, 48K, 160K, and 320K, work has begun on rolling themand converting them into unidirectional ribbon, but the problem of their transverse attachment arose. Many companiesknow how to correct this problem and are manufacturing such cloth, for example, the German company Epo GmbH ismanufacturing ribbon in fine polyester netting 300 mm wide, 0.1-0.75 mm thick, and 1 m2 weighs 80 to 800 g.

Fig. 2. World consumption of carbon fibres: 1) thermoplasts(electronics); 2) transportation (including ship building); 3) industry;4) infrastructure; 5) automobile construction; 6) oil rigs; 7) alternativeenergy (wind power); 8) sporting goods; 9) aviation and rocketconstruction.

81000

72000

63000

54000

45000

36000

27000

18000

9000

0

Con

sum

ptio

n, t

ons

2

3

4

5

6

7

8

2004 2005 2006 2007 2008 2009 2010Year

9

1

276

The developments of the last two to three years include production of wide bidirectional fabrics from previouslyrolled 12K and 24K carbon twists. The Japanese company Sakai Ovex, which constructed and manufactured specializedequipment for precision rolling of twists and laying them at a 90° angle to fabricate fabrics of a given width and thickness,has obtained good results in this respect. Fabrics 0.1-0.3 mm thick, up to 1000 mm wide, and weighing 120-320 g/m2 havebeen obtained by combining these operations.

AREAS OF APPLICATION OF CARBON MATERIALS

The areas of application of carbon fibre materials are determined by their properties, primarily elevated mechanicalproperties, low coefficient of linear expansion, high thermal stability and heat resistance, electric conductivity, and X-raytransparency.

Note that carbon fibres and fabrics are usually used as reinforcing fillers in production of the composite materials(carbon-fibre-reinforced plastics) from which different parts and structures are made. Epoxy, as well as polyester, phenol-formaldehyde, polyamide, and polypropylene resins, are most frequently used as the binders.

The fundamental areas of application of carbon materials are aircraft and rocket construction, automobile construction(body parts, Cardan shaft, gas tanks), textile machine building (loom frames, rapiers), energetics (wind turbine blades,cables), construction (creation and repair of bridges, tunnels, buildings, columns), medicine (prostheses, bandages, X-ray-transparent patient beds, X-ray holders), sporting goods (skis, ski poles, fishing rods, boats, oars, bicycle frames, golf clubsand hockey sticks, racquets), oil rigs; office equipment frames.

TABLE 6. Composition of PAN-Based Carbon Fibre Materials Manufactured in Russia

Carbon fibres and twists

Brand of material Linear density of fibre, t ex

Density, kg/m

3

Properties in epoxy carbon-fiber-reinforced plastic

strength, GPa mod ulus of elastici ty, GPa density, kg/m3

tensile compressive

UKN-M (2,5K*, З K, 5 K, 6 K, 12 K, 6 K, 12 K) 120-720 1750±40 1.4-1.7 1.1-1.2 120-140 1450

Grapan (2,5 K *, З K, 5 K, 6 K, 12 K) 100-700 1720-1800 1.1-1.2 0.6-0.8 150-230 1500-1650

UK-30 (320 K) 30000 1750±40 0.8-1.0 0.6-0.8 90-120 1450

Unidirectional carbon ribbon

Brand of material Width, mm Surface

density, g/m2

Properties in epoxy carbon-fiber-reinforced plastic

strength, GPa modulus of elasticity, GPa

monolayer thickness, mm ten sile tensile

LU-P -01 255±20 30+5 0.6-0.7 0.6-0.7 157±25 0.11+0.01

LU-P -02 255±20 35±5 0.6-0.7 0.6-0.7 157±25 0.12±0.01

ELUR -P 245+30 30+5 0.8-0.9 0.8-0.9 145±20 0.11±0.01

ELUR -008- P 220±20 15±5 0.9-1.0 0.9-1.0 145±10 0.08±0.01

LZh U -M-12 250+20 30+2 1.0-1.2 0.8-0.9 130+10 0.12±0.015

LZh U - M-15 250+25 30±2 1.0-1.2 0.7-0.8 160±10 0.12±0.015

Carbon and combined and wo ven structures made from UKN fibres

Material Width, mm

Surface density, g/m

2

Properties in epoxy carbon-fiber-reinforced plastic

strength, GPa modulus of elasticity, GPa

monolayer thickness, mm

tensi le t ensile

Carbon fabric UT 400-900 200-450 0.6** 0.6** 60** 0.20-0.35

Combined ribbon UOL* 300 60-100 1.3 1.0 120 0.17-0.25 ______________ *Warp – carbon fibres; weft – organic or glass fibres. **Values over warp and over weft.

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As indicated previously, aerospace engineering increased orders by 19-20% in 2010. The energy sector could besecond in consumption since wind turbines are being built at high rates. Manufacturers of offshore-drilling platforms andbuilders, especially in seismic zones, are showing great interest in these materials. Use of fibres in sporting goods shouldincrease by 5-8%.

The total consumption of carbon materials in 2010 is estimated at 70-80,000 tons (Fig. 2).

REFERENCES

1. W. Watt, J. N. Phillips, and W. Johnson, Engineer (London), 221, 815 (1966. Leading Manufacturers.2. JEC, Composites, No. 1, 40-43 (2003).3. JEC, Composites, No. 1, 26-29 (2003).