Pultruded composites

Thermoformed chassis and body panels are featured on the car. The products were made initially in the USA for assembly in China. The car will weigh less than 2000 lb (900 kg). Automotive Design Composites, Inc of San Antonio, TX, designed the vehicle to have body panels and trunk formed from coextruded sheet of ABS with an ASA cap layer that will hang on a pultruded composite frame. Ceramic tooling is used to thermoform plastic products. 

Boukhili, B., Hubert, P. and Gauvin, R. (1991). Loading rate effect as a function of the span-to-depth ratio in three-point bend testing of unidirectional pultruded composites. Composites 22, 39-45. 

Figure 11.3 Applications of pultruded composites in the United States, Japan, and Europe in 1991 [2]...

The most spectacular application example to date is perhaps the Aberfeldy footbridge over the river Tay in Scotland (see Fig. 11.4). This bridge is 113-m long, has a deck width of 2.2 m, and a main span of 113 m [4]. The entire deck structure, hand rails, and A-frame towers are pultruded composites, and the cable stays are Kevlar ropes. The deck structure is assembled from a modular system of pultruded 6-m long, hollow components, which consist of 70 percent by weight of E glass and 30 percent pigmented isophtalic polyester resin. 

Despite the excellent stiffness- and strength-to-weight ratios obtainable in pultruded composites, it is interesting to note that more than half of all pultruded composites were probably sold for nonstructural applications (cf. Fig. 11.3). 

A S Mosallam and R E Chambers, Design procedure for predicting creep and recovery of pultruded composites , Proceedings of the 50th Annual Conference, Composites Institute, Cincinnati, USA, Paper 6-C. New York, The Society of the Plastics Industry, January 1995. 

D. W. Fallis and R. P. Kusy, Variation in flexural properties of photo-pultruded composite archwires Analyses of round and rectangular profiles, Journal of Materials Science Materials in Medicine 11 683-693 (2000). 

Jones BH, Jakway W, Goldsworthy Engineering Inc, MM T—Pultruded composite structural elements, US Army Aviations systems Command Final Report, USAAMRDL-TR-76-5, Dec 1976. 

In the case of reinforcements with pultruded composite materials performed directly in the processing plant, the geometry of the pultruded sheets can be chosen among those realized by the producers. In the case of pultruded composite materials, the percentage of fibers in the composite material usually does not exceed 65 %. Even if the mechanical properties of the composite materials are mainly given by the fibers, the properties of the matrix are also very important. For this reason, it is important to use resins characterized by very high mechanical properties, such as the epoxy resins. 

Table S.1 Geomebical and physical properties of the pultruded composites (CSLX.PP guidelines)...

Table 8.2 Mechanical properties of pultruded composites (CSLLPP guidelines)...

Low production cost Studies on products requiring optimum fibre placement and part performance have shown that pultrusion cost is about 41% of the filament winding and 26% of the prepeg hand lay-up (Krolewski and Gutowski, 1986 Strong, 2002). About 80-90% of the cost of pultruded composites comes from the raw materials it uses. The amortized machine cost and the labour to run pultrusion machines make up only small portion of the total factory costs. 

The pultruded composites mainly consist of continuous fibrous reinforcement, polymeric matrix, fillers and additives. 

According to the curing kinetics and the heat transfer theories, Chen et al. (2010) established the models for unsteady field of temperature and curing. The finite element method (FEM) and FDM were combined, and the indirect decoupling method based on ANSYS was adopted to simulate the temperature profile in pultrudate composites during pultrusion. 

The pultrusion industry has been growing and the growth is driven by newer applications for pultruded composites. Advances in materials and innovations in the process have enabled manufacturers to design new or improved products (Busel, 2008). 

In 2007, ACMA (American Composites Manufacturers Association) and ASCE (American Society of Civil Engineers) jointly developed an LRFD (Load Resistance Factor Design) standard for pultruded composites. LRFD refers to a design methodology that makes use of load and resistance factors based on the known variability of applied loads and material parameters. The development of the LRFD standard is expected to significantly influence the universal acceptance of pultruded composites (Busel, 2008). 

The global market for pultruded composites is 250-300 metric tons (Owens Corning, 2009), which account to about 1.2 billion (year 2004 estimate). The market spread amounts to approximately 40% in the Asia Pacific region, 40% in North America and 20% in Europe. As of 2010, there were more than 300 pultruders in the world, but many of them operate on a smaller scale (Jacob, 2006). In terms of the revenue generated by pultrusion products, Exel, Strongwell and Werner make the top three pultruders in the world currently. 

Black, S. (2004), Pultruded composite sheet pihng replace degraded wood piUngs , Composites Technology, Fehruary. 

Another use of LCM techniques is in the manufacture of cuff links to improve the assembly of pultruded composite beams and components [159]. As part of the electrification of the rail network in New Zealand, Kiwirail is using the RTM process to manufacture screens to be placed on bridges over the rail lines to protect pedestrians and prevent any contact with the electric lines. 

The product development of pultruded composites offers an enormous diversity of possibilities, sinee a wide variety of resins, additives and fillers can be combined for use in the matrix, with several reinforcing fibres (type, content, orientation, arehiteeture). The philosophy underlying the development of FRPs has been to design materials for specific requirements (such as mechanical performance, lightness and ehemical resistanee) through a judicious combination of the above-mentioned eonstituent materials. 

Although fibre reinforcements are responsible for most of the mechanical performance of pultruded composites, the polymeric matrices must be able to bear some of the loads, particularly those in the transverse direction and shear stresses. Furthermore, the polymeric matrix has four essential functions (Keller, 2003) ... 

In addition to the base resin, the polymeric matrices of pultruded composites contain supplementary constituents (polymerisation agents, fillers and additives), used to induce the polymerisation reaction, to improve the material processing, to modify the properties of the final FRP product or simply to reduce the cost of the part produced. 

Pultruded composites can be produced in a large variety of colours, basically in line with the RAL classic chart, using colouring additives. However, completely homogeneous pigmentation is not always possible since glass reinforcement has no pigment tolerance (Barefoot, 2007). 

With regard to the service life use, FRP pultruded composites are more environmentally friendly than most traditional materials they need very little maintenance and, as previously discussed, exhibit improved durability even in relatively harsh environments. Furthermore, when used in building applications, the low thermal conductivity of FRPs may be associated with potential energy savings (the Eyecatcher Building stands as an example of this advantage). 

In terms of eonstituent materials, new types and forms of fibre reinforcements are likely to be introduced. In relation to this it is worth mentioning basalt fibres as an emerging alternative to the reinforcement of FRP pultruded composites. Although the manufacturing cost of basalt fibres currently exceeds that of E-glass fibres (Ross, 2006), the mechanical properties of... 

Barefoot G (2007), Color matching for pultruded composites. Obstacles and answers . Composites Manufacturing, June, 38-40, 41 2. 

Kalamkarov A L, Fitzgerald S B, MacDonald D O and Georgiades A V (2000), The mechanical performance of pultruded composite rods with embedded fiber-optic sensors . Composites Science and Technology, 60(8), 1161-1169. 

This section lists selected information sources on pultruded composite materials, processing and structures. 

Zhang Y, Vassilopoulos A Pand KellerT (2010a), Mode I and mode II fracture behavior of adhesively-bonded pultruded composite joints. Engineering Fracture Mechanics, Vol. 77, No. 1, pp. 128-143. 

A waterborne, thermally cured phenolic resole specially developed for use in the manufacture of pultruded composite parts, a. 1.21-1.23 b. 75-78% c. 5000-7000cps... 

The void content of pultruded composite rods have been studied using NMRI [IS]. Glass fiber-reinforced nylon rods with fiber contents of 51% by volume were first mixed with different catalyst contents following the reaction injection molding (RIM) process, and then pultruded with a pulling speed 18 inches... 

Martin J. Pultruded composites compete with traditional construction materials. Reinf Plast. 2006 50(5) 20-27. 

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