ARAMID FIBRE-REINFORCED

Epoxide resins reinforced with carbon and Aramid fibres have been used in small boats, where it is claimed that products of equal stiffness and more useable space may be produced with a 40% saving in weight over traditional polyester/ glass fibre composites. Aramid fibre-reinforced epoxide resins have been developed in the United States to replace steel helmets for military purposes. Printed circuit board bases also provide a substantial outlet for epoxide resins. One recent survey indicates that over one-quarter of epoxide resin production in Western Europe is used for this application. The laminates also find some use in chermical engineering plant and in tooling. 

Short glass fibre reinforcement the main thermoplastics are offered in such grades. Some short carbon or aramid fibre reinforced resins are also marketed. 

Table 6.9 shows the enhancement ratios for aramid fibres versus glass fibres used in the same composite type. The enhancement ratios are the ratios of a property for an aramid fibre reinforced composite versus the same property for the glass fibre reinforced composite. 

In this respect, (thermoset) plastics composites with discontinuous fibre products are already mostly used in the car body applications, where polyester/E-glass is predominating (mostly because of polyesters, economy, ease of processability and reasonable mechanical properties provided), followed by use of phenolics (when fire retardance is required, in friction linings and engine compartments), and epoxies. Replacement by carbon or aramid fibre reinforcements can reduce body mass by 40% (compared to steel) and with more added strength, but the cost is unfavourable at the moment, as mentioned previously [12, 13]. 

L G P Dalmolen, J Willing, A Goksoyr and P Osen, Para-aramid fibre-reinforced composite bellmouths for a floating production platform . Conference on Structural Materials in Marine Environments, London, loM/MTD/IMechE/ IMarE, 11-12 May 1994, pp 109-118. 

Resin transfer moulding (RTM) is a low-pressure variation of transfer moulding where, instead of granules or preforms, a pre-mixed resin and catalyst (hardener) is injected into a closed mould containing dry glass, carbon or aramid fibre reinforcement. When the resin has cooled, the mould is opened and the composite part ejected. The resins used include polyester, vinylester, epoxies, phenolics and methyl methacrylate combined with pigments and fillers. Applications include small complex aircraft and automotive components as well as automotive body parts, baths and containers. 

Klein N, Marom G, Wachtel E, Microstructure of nylon 6,6 transcrystalline layers in earbon and aramid fibre reinforced composites. Polymer, 37(24), 5493-5498, 1996. 

AFRP Aramid-fibre-reinforced polymer composites... 

Cover micrograph of aramid fibre-reinforced polyamide 6,6, reproduced with permission from... 

Correa and co-workers [a.272] studied the thermal behaviour of short-fibre-reinforced PU composites by DSC and TG techniques and reported that the thermal resistance of aramid-fibre-reinforced composites was greater than that of carbon-fibre-reinforced composites or the pure matrix polymer. The DTG results are presented in Figure 31. 

FML materials are the most recent substrates to be used in aircraft construction. The first products, initially designated Arall (aramid fibre reinforced aluminium laminates). Glare (glass fibre reinforced aluminium laminates) and... 

Hofste JM, Schut JA, Pennings AJ. The effect of chromic acid treatment on the mechanical and tribological properties of aramid fibre reinforced ultra-high molecular weight polyethylene composite. J Mater Sci 1998 October 9(10) 561-6. 

Fig. 8. Comparison of compressive and tensile properties of unidirectional carbon and aramid fibre reinforced composites.

A. Nanni, Properties of aramid fibre reinforced concrete and SIFCON, ASCE J. Materials in Civil Engineering. 2,1992,1-15. 

MICROMECHANICAL ANALYSIS OF INTEREACIAL SHEAR STRENGTH OF ARAMID FIBRE REINFORCED THERMOPLASTIC ELASTOMERS. 

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