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Composites: World Markets and Opportunities Amanda Weaver, Editor-in-Chief, Reinforced Plastics

The general public, and those that should know bet ter such as engineers and designers, tend to have two per- cept ions of composites: ei ther as fibre- glass - a rather second-rate material used to make kit cars; or as an esoteric carbon fibre based material used only in fighters and stealth bombers . Both percept ions are wrong. The reality is that nearly 5 million tonnes of ther- moset composi tes were used world- wide in 1997 in applicat ions as diverse as bridges, boats, cars and windmills represent ing a global business wor th some $120 billion.

And it will get bigger in the future. Historical analysis shows that the com- posites industry has averaged growth rates a round twice those of gross domestic product (GDP) in western countries over the past three decades and there is every indication this will continue. The USA has recorded seven consecutive years of record c o m p o s i t e s shipments and this is from a market that cynics argue is reaching maturity.

Industry forecasts suggest that com- posi tes shipments will approach 6 mil- lion tonnes by the end of the century wi th growth coming from two direc- tions: the increasing use of composi tes in es tab l i shed app l i ca t ions by the deve lop ing regions of Asia-Pacific, Eastern Europe and Latin America; and the new applicat ions for composi tes in their deve loped markets.

Looking at the geographical oppor tu- nity first: North America and Europe are still the dominant markets, wi th shares of 35% and 27% respectively, but faster growth rates in Asia-Pacific before the economic crash had indi- ca ted that the region would overtake Europe as the world ' s second largest composi tes market by the end of the century. This n o w looks less likely but the long term potential for composi tes

is significant. Consumption of compos- ites in Asia-Pacific is current ly less than 0.3 kg/head, compared wi th 8.5 kg in North America, 4.5 kg in Japan and 3.5 kg in Western Europe. But as markets and technology develop this is likely to increase more than tenfold. The growth will s tem from applicat ions resulting from the region's developing infrastructure and demand for a higher standard of living.

It is est imated thatAsia needs to spend $270 million a day to upgrade its infra- structure: building panels, cladding and modular housing; environmental pro- tect ion products such as seawalls, con- ta inment and storage tanks, corros ion resistant access systems and pipes; and a whole range of products associated wi th vehicles and structures for trans- por t systems.

For instance, composi te p ipe looks set for s ignif icant g rowth . The h igh demand for n e w infrastructure and an increased living standard for the pop- ulation makes the region a key mar- ket, says Owens Corning Engineered Pipe Systems. Over the past three years, O w e n s Corn ing Changchun Guan Dao Co Ltd has suppl ied nearly 100 km of GRP p ipe in the nor th east of China. During 1996 the Changchun facility was awarded a contract to sup- ply p ipe (610 bar pressure class) for a 17 km line in Yonfji, in the Jilin province. The pipel ine n o w supplies the ci ty 's 200 000 res idents wi th potable water.

The market for composi tes in con- struction and civil engineering appli- cations is also set to benefit fromAsia 's growth. The cons t ruc t ion sec tor is already the world 's largest consumer of composites. With a market share of 35% it is as large as the next two biggest sectors, t ransport and electri- cal, a d d e d together . It is also an

expanding area, through rep lacement of ageing infrastructure in deve loped regions as well as n e w deve lopments in emerging countries.

The US infrastructure is est imated to be in need of a $90 billion facelift and c o m p o s i t e s are being used in applica- tions as diverse as the reinforcement of bridge suppor ts damaged by earth- quakes; replacements for deteriorating concrete bridge decks; reinforcing bars for use in concrete subject to highly corrosive environments; seawalls in marinas and waterfront areas; and dock fenders to replace rotten w o o d e n ones.

Engineers responsible for the design of next generat ion infrastructure are turning to composi tes based on the life cycle cost benefits they offer com- pared wi th tradit ional material sys- tems. They are insisting on materials that provide longer service life, l ower main tenance cost and c o m p o n e n t s that are easy to repair. Al though com- posi tes are more expens ive than tradi- t ional materials such as concre te , steel and wood, they offer a number of advantages. Their l ight weight means they are cheaper and easier to trans- po r t and install. Their inherent corro- s ion res is tance no t only increases their durabil i ty but it reduces the need for maintenance throughout the struc- ture 's life. A number of recent installa- t ions illustrate the change in at t i tudes towards compos i tes of the big utility companies and civil engineer ing bod- ies. One is a demons t ra t ion pro jec t using compos i t e electr ical transmis- s ion towers on California 's Pacific coast l ine (FIGURE 1). In the project , wh ich is sponsored by two large US e lec t r i c uti l i t ies, t h r ee t ower s des igned to suppor t high voltage elec- tr ic p o w e r t ransmission lines have been installed at a p o w e r generat ion plant.All structural c ompone n t s of the 26.5 m high towers were pu l t ruded

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using low-cost fibreglass wi th a vinyl-ester resin matrix. Manufacturer Ebert Composi tes says that the towers are approximately one-third the weight of a steel version and are more easily and rapidly assem- bled, transported and erect- ed than steel ones.

Changes in the approach of civil engineers can also be seen in the area of bridge construct ion. The original bridge crossing the UK's Severn Estuary, constructed in the 1960s, used hardly any composites. In contras t extensive use of composites has been made on the new bridge which o p e n e d in June 1996. The M4 motor- way approaching the bridge is carried over roads and a railway by a total of n ine bridges. These have all been

completely clad in compos- ites using Maunsell Structural Plastics' Caretaker bridge enclosure system (FIGURE 2). This features a pul t ruded plank along the base of the enclosure with the curved section formed from continu- ous laminated sheet.The system offers two advantages. It protects the

bridge's structure with a corrosion- resistant composite envelope, reduc- ing the need for exterior maintenance and the enclosure is also sufficiently strong to provide an access gantry for all maintenance work on the bridge.

Other applications for composites on br idges inc lude the various tech- niques for wrapping freeway suppor t co lumns in California, some of which

have n o w b e e n commerc ia l ly approved by the California Transport Depar tment (Caltrans). In some cases the columns are wound in-situ using a robo-winder whereas other solu- t ions inc lude th in prefabr ica ted composi te jackets which are glued in place (FIGURE 3).

The use of carbon fibre sheets to pre- vent further cracking on concre te bridges is also beginning to find appli- cations.The technology was developed

by Dr Urs Maier of EMPA in Switzerland and is being employed in several applications in that country. The latest project from Maier's team is for a carbon fibre reinforced plastic (CFRP) cable stayed bridge. Maier says

that the CFRP cables have excellent behaviour with respect to corrosion

and fatigue, and are five times

lighter than steel cables.

Composite bridge decks are also under development. The 7.1 m long, 11 tonne bridge, which spans No-Name Creek in Russell County, Kansas, USA, is the first field demonstration of Kansas Structural Composites Inc's tech-

nology for rapid replacement, short span bridges.The bridges are strong enough for vehicle traffic yet light enough to allow major sections to be factory built and shipped quickly to the site. Using small cranes, a replacement bridge up to 10.7 m long can be installed in 8-16 hours on previously com- pleted support structures.

But the use of composites in bridges is not restricted to decks or cladding. It is also being com- prehensively demonstrated by the Fiberline Bridge in Kolding, Denmark, which opened in June 1997 (FIGURE 4).The only non- composites parts on the bridge are the bolts holding it together.

Composites offered a number of advan- tages over traditional materials for this bridge, which wiU carry cyclists and pedestrians over a main railway line. They are non-conductive and therefore safe in proximity to the overhead elec- tric lines. They are non-corrosive and will not be attacked by salt water blow-

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ing off the adjacent tjord. The bridge is estimated to need only cosmetic main- tenance for the first 50 years of its life.

The 38 m span bridge weighs just 10 tonnes, less than half the weight of steel construction, making installation and transport easier and cheaper. In fact it was possible to install the bridge in just a few hours over two weekends.

Waterfront areas are also providing good opportuni t ies for composites, thanks to their inherent corrosion resistance. Applications include piers, seawalls and dock fenders. The initial application for dock fenders was for six prototypes for the Delaware River and Bay Authority (DRBA). These were fabricated by Hardcore DuPont during 1994. The DRBA had previously used steel fenders to protect its docks which made ferry docking a jarring experience for passengers. The steel fenders also suffered from corrosion. The Hardcore DuPont solution was developed after evaluating technology

used by the US Navy. The result is com- posite fenders which absorb greater impacts, do not corrode and do not cause any environmental contamina- t ion of the water.

Throughout the summer of 1994 the system was tested in the field absorb- ing the impact of more than 900 ferry landings. Following the success of the prototypes the DRBA placed an order for 84 fenders to completely refit the ferry terminal. The fenders have also been specified in the Port of Buenos Aires and proposed for the Port of Los Angeles.

The fenders are made by the SCRIMP (Seemann Composites Resin Infusion Manufacturing Process) the current favoured by the US indsutry 'hot ' process.The principle, using a vacuum to suck resin through a glass mat in a single shell mould with a back surface provided by a vacuum bag, is not par- ticularly new. However, it is being clev- erly p romoted and at tract ing the

attention of many fabricators of large contact moulded parts who want to

reduce styrene emissions. In the USA the SCRIMP, and other resin infusion processes, are being used to make boats and rail freight cars. One such is

the CrayValley CCP, a 15.2 m long rac- ing yacht, which will compete in the 1998 single-handed, round-the-world race. The boat, built by North End Composites , has a solid ca rbon f ib re /epoxy laminate hull wh ich weighs about the same as a sandwich

construct ion but is much bet ter able to withstand the slamming loads the yacht will encounter w h e n sailing at

high speed.

In Europe, Vosper Thornycroft (VT) is using SCRIMP to fabricate the super- structure of its latest Royal Navy mine- hunters . VT claims that by using

SCRIMP it can produce better quality parts than with hand lay-up while

reducing costs and styrene emissions. The firm can incorporate up to 72% fibre by weight in the laminate using glass woven roving. It can also achieve less than 1% voids across the laminate, compared with around 5% or more for hand lay-up.VT has made SCRIMP lam- inates up to 100 m3 in area and up to

20 m long.The minehunter superstruc- ture panels are typically 10 m 2 and

weigh around 2 tonnes. Because they have a higher fibre volume content than w h e n they were made by hand lay-up the resin con ten t can be reduced, cutting costs. Production is also quicker and less complicated than using hand lay.The manually produced

panels can require up to 35 separate plies of woven roving to be laid up individually. In SCRIMP much heavier fabrics can be used instead because the improved resin infusion is inde- penden t of fabric weight.

While some of the claims made for SCRIMP may be "hype", the need to

develop processing techniques which produce high quality parts at reasonable cost for moderate size runs while reduc- ing styrene emissions, is real enough. Workplace restrictions in styrene emis-

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Composites: Market! 1 o e o ~ . . . . .

sion are 50 ppm through much of Europe failing to as low as 20 ppm in some countries. But it is no longer acceptable to vent excess

styrene from the factory to the external air, particularly in Scandinavia and California. Many

contact moulders are therefore presented with a choice of finding an alternative fabrication tech- nique or installing extremely expensive air cleaning systems to comply with legislation.

, .

The availability of low styrene resins and gel-coats goes a long way towards alleviating environ-

mental problems but does not com- pletely solve them. New processing techniques are also needed. Resin infu- sion is a good first step in many cases offering low emissions and higher qual- ity products for a moderate capital investment. It is also said to be a more 'user friendly' process than other closed moulding techniques such as resin transfer moulding (RTM).

But RTM should not be dismissed, the technique is finally beginning to real-

ize its potential. Commercial develop- ments such as the Fiesta spoiler from Sotira and large bus and truck parts from some Brazilian moulders show that it can be used to make both high volume and large parts economically.

The technology has also been devel- oped to the extent that Plastech is happy to claim that it can offer a 100%

emission-free system. The resin is enclosed all the way from the drum until it is cured in the mould.

Developments in the more traditional

compression moulding of sheet mould- ing compound (SMC), including low

pressure resins, in-mould coating tech- niques and improved paint technology, are once again making the process extremely attractive to car makers. DSM Compounds reports that in the US

SMC is the fastest growing automotive plastic and is increasingly replacing the use of steel in trucks and cars. The ben- efits which make it such a success go beyond its ability to reduce weight, says the firm.

In Europe the car industry is becom- ing more and more fragmented with

lots of volume car makers looking to produce a variety of niche cars with different bodies on the same plat- form. A number of leading European car makers including Mercedes, BMW and Porsche, have been s tudying recent US SMC developments eagerly.

Japanese car makers have also been slow to adopt SMC in the past because of their strong links with the steel mak- ers. But as Asia's car industry moves out of Japan to countries with lower labour costs and no traditional metals indus-

try, SMC could find favour.

For instance, Korean car makers are known to be making use of glass mat thermoplastics (GMT) in a variety of applications. This material first hit real prominence in Europe with its appli- cation in the structural front end of t h e

VW Golf A3 in 1991.VW has cont inued to develop the use of GMT front-ends with variants now found in several Audi models and the VW Polo.

More recent developments go one step further eliminating the prepreg stage. Menzolit Fibron has pioneered this with its long fibre reinforced ther- moplastic technology (LFT) which is plasticized and compression moulded in one step. Other deve lopments announced recently look to take this technology even further in terms of structural automotive parts. One of these is a joint venture be t w e e n Owens Coming and DSM Automotive which uses 'cable' type technology to make a polypropylene c o m p o u n d which includes glass fibres up to 10 mm long which can be pelletized and

injection moulded in standard machinery used by the thermo- plastics processing industry.

But the major growth in auto- motive composites is likely to come from unde r - t he -bonne t

appl icat ions. Reinforced ther- mosets and thermoplastics are used to produce a range of parts including valve covers and noise shields. But the mos t highly deve loped appl ica t ion is the short fibre reinforced nylon air intake manifold (FIGURE 5). Industry insiders estimate that p roduct ion of polyamide (PA)

resin for the application could reach 45 000 tonnes/year by the end of the decade, almost triple that for 1996.

The first reinforced nylon inlet mani-

fold, for the Porsche 911, was in fact commercialised as long ago as 1972. But it is only in recent years that they have become c ommonp l ace in European cars. Plastic manifolds are cheaper to make than metal ones,

weigh less and the smoother internal profiles possible with injection mould- ed nylon compared with metal mean that the manifold is more efficient.

Although the compos i tes indus t ry faces threats from both its need to become a cleaner technology and from advances in traditional materials, such as new lightweight steels, to predict its demise would be premature.

Growth over the next two years in Western Europe and North America is likely to be modest rather than excep- tional, although significant n e w appli- cations are likely to become commer- cial reality. Asia-Pacific, and o the r developing regions, has b e e n expect- ed to show much faster growth, bu t the economic crisis affecting many of these regions has halted this for the t ime being. However, in the med ium term Asia-Pacific will be a major user of composite materials in a diverse range of applications. Indust ry fore- casts indicate that a l though the rate of composites indust ry growth will s low slightly t h e r m o s e t materials alone can expect to approach ship-

ments of 6 million tonnes by the end of the decade.

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