Carbon fibre reinforced composites material properties

Whitney JM, Browning CE (1978) Some anomalies associated with moisture diffusion in epoxy matrix composite materials. In Vinson JR (ed) Advanced composite materials-environmental effects, ASTM STP 658. American Society for Testing and Materials, Philadelphia, pp 43-60 Wright W (1981) The effect of diffusion of water into epoxy resins and their carbon-fibre reinforced composites. Composites 12(3) 201-205 Yao J, Ziegmaim G (2007) Water absorption behavior and its influence on properties of GRP pipe. J Compos Mater 41(8) 993-1008... 

No water is produced in the reaction and the shrinkage on curing is small. Fillers are often added to improve the electrical and mechanical properties, and epoxy resins are becoming increasingly used as matrix materials for high performance carbon-fibre reinforced composites. 

Here P is the load on the column or panel, L its length, p the specific weight and E the compression modulus of elasticity. The material efficiency criterion depends thus only on material properties and Fig. 8 shows that this criterion for columns made from aramid almost equals that of carbon fibre reinforced composites. 

Figure 3.16 Tensile strengths of reinforced Type II electroplated and hot-pressed copper. Broken line as predicted by Law of Mixtures. Source Reprinted with permission from Howlett BW, Minty DC, Old CF, The fabrication and properties of carbon fibre/metal composites, Paper No. 14, International Conference on Carbon Fibres and Applications, The Plastics Institute, London, 1971. Copyright 1971, Maney Publishing (who administers the copyright on behalf of lOM Communication Ltd, a wholly owned subsidiary of the Institute of Materials, Minerals Mininng).

Loos (2011) reported that investigators from Bayer Material Science LLC, USA and Moulded Fibre Glass, Cleveland, USA have developed a prototype wind turbine blade 0.74 m long manufactured from polyurethane reinforced with carbon nanotubes (CNT PU). The researchers claim that the advanced material has a specific tensile strength five times and 60 times that of carbon fibre composite and aluminium, respectively, and is tougher than carbon fibre-reinforced polymer (CFRP) but the excellent properties of these materials come with a price penalty. 

In our minds, the suitability of C/C composites as armaments for magnets in fusion technology should be proved. First steps in this direction were done by investigating the thermal properties of carbon-fibre-reinforced carbon composites at low temperatures. Because of the chemical and physical properties of carbon, along with the various parameters that influence the properties of this composite material, it seems possible to tailor a material to the special requirements of that application. 

Weiss W (1982), Low temperature properties of carbon fibre reinforced epoxide resins , in Hartwig G and Evans D (eds) Proceedings of the 2nd ICMC Symposium on Non-metallic Materials and Composites at Low Temperatures, New York Plenum Press, 293-309. 

Lin, T., Jia, D., He, R, Wang, M., Liang, D., 2008. Effects of fibre length on mechanical properties and fracture behavior of short carbon fibre reinforced geopolymer matrix composites. Materials Science and Engineering A, 497(1-2), pp. 181-185. 

The properties of composites determine the processing techniques used, and these can be very different indeed. The two poles of the spectrum of composites are represented on the one hand by materials suitable for high speed conversion processes, such as injection-mouldable reinforced nylon, and on the other hand by materials used for high strength structures in very small numbers, like glass reinforced polyester for the hull of a minesweeper or carbon fibre reinforced epoxy for an airframe. 

Not long ago, the terms high performance composites and advanced composites were applied only to such composite materials as carbon fibre reinforced plastics and metal matrix composites, used in the construction of aircraft, rockets and satellites. These terms are now used for concrete-like materials and have similar meaning they are materials of improved selected properties, designed and produced for special applications. The concept of high performance is expressed by the following technical terms ... 

These properties of carbon fibres from mesophase pitch are very advantageous for carbon/carbon composites (carbon fibre reinforced carbon materials CFRC), which are mostly of military importance today in the missile technology. In spite of intensive studies on further advantageous applications it can not yet be seen where these pitch based fibres are superior for fibre reinforced plastics. Even the present prices do not beat those of PAN based fibres especially if heavy tows are con -sidered. 

So far when considering carbon fibre composites the matrix has been a thermosetting resin or polymer. The relative merits of thermosetting and thermoplastic polymer matrices were discussed briefly in Chapter 3. Several thermoplastic matrices are compounded with short carbon or glass fibres. In Table 5.22 however the properties of unidirectional, continuous, carbon fibre-reinforced materials are illustrated. 

The thermal properties of fibre-reinforced composites are anisotropic. Expansion in the direction of the fibre is usually very small or negative, but the thermal conductivity of some carbon fibre composites in the fibre direction can be high. Most polymers and several types of fibre are good electrical insulators. Carbon and some ceramic fibres have a much lower resistivity. It is thus possible to use composites for manufacturing radomes as well as for electromagnetic screening materials and systems which absorb radar signals. 

As a result of their outstanding physical and mechanical properties, aromatic polyamides are attractive materials for use in high-performance structural applications 853072 833611 820253, including aircraft components or fire protection garments, as constituents of both traditional, i.e., fibre-reinforced composites 774110 762844, and molecular composites. One of these applications takes advantage of their thermal stability 881232 825031 763791 755849 and allows the manufacturing of heat-resistant materials for fire protection 713906. In a different context, aromatic polyamides (aramid fibres) have been proposed in the past few years as precursors of activated carbon materials with distinctive adsorbent properties (thermally stable molecular sieves). Aramid fibres, e.g., poly(w-phenylene isophthalamide), poly(p-phenylene terephthalamide) 709654, etc., are a class of synthetic polymers that possess excellent thermal and oxidative stability, good flame resistance, and superior mechanical and dielectric behaviour. 

J. D. Haan, R. Reber, J. Mayer, E. Wintermantel (1998) Tensile properties of plain weft knitted carbon fibre reinforced polyamide 12 composites. First Asian-Australasian Conf. Composite Materials (ACCM-1) Vol. 1, p. 403. 

It may be useful to the reader to consider as an example the work by Adams et al (1978c) and some of their hitherto unpublished results. They used finite-element methods to examine the stresses in high-performance composites in symmetrical lap joints with parallel, bevelled, scarfed and stepped adherends. The composite adherends were assumed to be linearly elastic type II carbon fibre reinforced epoxy composites with a 60% fibre volume fraction. The mechanical properties of this material are given in Table 3. 

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