Carbon fibers reinforced epoxy

The results presented below were obtained using a 2 mm thick carbon fiber reinforced epoxy composite laminate with 16 layers. The laminate was quasi isotropic with fiber orientations 0°, 90° and 45°. The laminate had an average porosity content of approximately 1.7%. The object was divided in a training area and an evaluation area. The model parameters were determined by data solely from the training area. Both ultrasound tranducers used in the experiment had a center frequency of 21 MHz and a 6 dB bandwidth of 70%. 

Eig. 10. The variation of the density of carbon-fiber reinforced epoxy resin with the fiber volume fraction, based on the rule of mixtures. 

Fig. 12. (a) The variation of the tensile strength of unidirectional carbon-fiber-reinforced epoxy resin as a function of the fiber volume fraction, (b) The variation of the tensile strength of unidirectional carbon-fiber-reinforced epoxy resin as a function of the fiber volume fraction for low fiber volume... 

Davies, P. Kausch, H.H., Williams, J.G. and 29 other researchers (1992). Round-robin interlaminar fracture testing of carbon fiber reinforced epoxy and PEEK composites. Composites Sci. Technol. 43, 129-136. 

Bader M.G., Bailey J.E. and Bell 1. (1973). The effect of fiber-matrix interface strength on the impact and fracture properties of carbon fiber-reinforced epoxy resin composites. J. Phys. D Appi. Phvs. 6, 572-586. 

For example, the minimum fiber fraction for a carbon-fiber-reinforced epoxy matrix composite is 0.03. 

Figure 5.122 Strength chart for a (0, 9) unidirectional carbon-fiber-reinforced epoxy laminate composite. Reprinted, by permission, from N. G. McCrum, C. P. Buckley, and C. B. BucknaU, Principles of Polymer Engineering, 2nd ed., p. 408. Copyright 1997 by Oxford University Press.

Fig. 7. Comparison of stress-strain curves for carbon-fiber-reinforced epoxy composites of different thermal histories. Error rectangles were drawn to indicate a 95% confidence level for both stress and strain...

In order to study the effect of physical aging on the carbon-fiber reinforced epoxy, the freshly quenched materials were then sub-Tg annealed at 140 °C. After annealing for only 10 minutes at that temperature, the toughness of the composite was restored to a level comparable to that of the postcured material (see Fig. 7). It is likely that residual thermal stresses resulted from the quenching were annealed away during this 10 minutes thermal aging at 140 °C. 

Fig. 9. Effect of sub-Tg annealing on the ultimate mechanical properties of carbon-fiber-reinforced epoxies...

The fabrication of components from advanced composite materials also requires suitable tooling to shape and conform the prepreg during lay-up and epoxy have a role to play in this operation as well. Whilst less durable than conventional tooling constructed from steel or aluminum, tooling prepared from carbon fiber reinforced epoxy resins offers lightweight and, most importantly, a good match with the... 

The use of epoxidized hyperbranched polyesters as toughening additives in carbon-fiber reinforced epoxy composites has been demonstrated... 

The use of epoxidized hyperbranched polyesters as toughening additives in carbon-fiber reinforced epoxy composites has been demonstrated (Boogh et al., 1995). Since a hyperbranched resin has a substantially lower viscosity and much shorter drying time than a conventional (less branched) resin of comparable molecular weight, hyperbranched polymers have been used as the base for various coating resins (Pettersen and Sorensen, 1994). 

Effects on Time-Dependent Properties of Carbon Fiber-Reinforced Epoxy Composites... 

Dynamic Mechanical Analysis. The effect of postcuring, quenching, and sub-T s.nnealing on the mechanical dispersion peaks of ( 5°)2c carbon-fiber-reinforced epoxy composites is shown In Figures 8 and... 

Figure 27 Shear storage modulus, G, and damping, G", as a function of temperature for a carbon fiber-reinforced epoxy adhesive cured at 120°C. 

Yazid YM, Cantwell WJ, Langdon GS, Nurick GN. The blast resistance of a woven carbon fiber-reinforced epoxy composite. J Compos Mater 2011 45 789-801. http // dx.doi.org/10.1177/0021998310376103. 

Kumar, B.G., Singh, R.P., Nakamura, T., 2002. Degradation of carbon fiber-reinforced epoxy composites by ultraviolet radiation and condensation. J. Compos. Mater. 36, 2713-2733. 

Abu Abu Bakar, M. A., Ahmad, S., Kuntjoro, W. Effect of matrix modification on the mechanical properties of short carbon fiber-reinforced epoxy composites. J. Reinforced Plast. Compos. 30 (2011) 357-361. 

Some general articles on the properties of carbon fiber reinforced epoxies have been published in the references given [14-16]. 

Patel SR, Patel RG, Physicomechanical properties of carbon-fiber reinforced epoxy composites, Polymer-Plastics Technology and Engineering, 31(7-8), 705-712, 1992. 

Patel SR, Patel RG, Carbon-fiber reinforced epoxy composites, Polym Int, 30(3), 301-303, 1993. Soni HK, Patel RG, Patel VS, Structural, physical and mechanical-properties of carbon-fiber-reinforced composites of diglycidyl ether of bisphenol-A and bisphenol-C, Angewandte Makromolekulare Chemie, 211, 1-8, 1993. 

Malquarti G, Berruet RG, Bois D, Prosthetic use of carbon fiber-reinforced epoxy-resin for aesthetic crowns and fixed partial dentures, Journal of Prosthetic Dentistry, 63(3), 251-257, 1990. 

Fredriksson M, Astback J, Pamenius M, Arvidson K, A retrospective study of 236 patients with teeth restored by carbon fiber reinforced epoxy resin posts. Journal Of Prosthetic Dentistry, 80(2), 151-157, 1998. 

Xiaojun Wang, Chung DDL, Short carbon fiber reinforced epoxy coating as a piezoresistive strain sensor for cement mortar. Sensors and Actuators, A71(3), 208-212, 1998. 

Xiaojun Wang, Chung DDL, Short carbon fiber reinforced epoxy as a piezoresistive strain sensor. 

Adherent Technologies Inc. [8] has developed a process for the reclamation of carbon fibers from carbon/epoxy composites. It has studied the depolymerization of thermoset carbon fiber reinforced epoxy matrix composites using a low temperature (20 min at 325°Q catalytic tertiary recycling reclamation process and has been able to obtain a product with 99.8% carbon and 0.2% residual resin, with only a loss of about 8.6% in fiber tensile strength. The process can be economically viable, provided sufficient scrap feedstock is available. Possible applications for the recovered fiber include thermoplastic and thermoset molding compounds. 

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