Study on the Mechanical Properties and Creep Behaviour of Carbon Fiber Nano-Composites

Abstract:

Article Preview

The surface modification of carbon nanotubes(CNTs)has been recently observed to influence the distribution of CNTs in epoxy resin and the mechanical properties and electrical conductivities of these CNTs. Accordingly, the treatment of CNTs to with organic acids to oxidize them generates functional groups on the surface of CNTs. This investigation studies the consequent enhancement of the mechanical properties and electrical conductivities of CNTs. The influence of adding various proportions of CNTs to the epoxy resin on the mechanical properties and electrical conductivities of the composites thus formed is investigated, and the strength of the material is tested at different temperatures. Moreover, the creep behavior of carbon fiber(CF)/epoxy resin thermosetting composites was tested analyzed at different stresses, orientations of fiber, temperatures and humidities. The creep exhibits only two stages- primary creep and steady-state creep. The effects of creep stress, creep time, and humidity on the creep of composites that contain various proportion of CNTs were investigated at various temperatures. However, increasing the number of cycles in cyclic creep tests at room temperature resulted in a decrease in creep strain even at a high temperature of 55°C. Possible room temperature creep mechanisms have been proposed and discussed. Creep strain is believed to increase with applied stress, creep time, humidity, temperature and degree of the angle θ between the orientation of fiber and the direction of the applied stress. The test results also indicate that mechanical strength and electrical conductivity increase with the amount of CNTs added to the composites. Different coefficients of expansion of the matrix, fiber and CNTs, are such that overexpansion of the matrix at high temperature results in cracking in it. An SEM image of the fracture surface reveals debonding and the pulling out of longitudinal fibers because of poor interfacial bonding between fiber and matrix, which reduce overall strength.

Info:

Periodical:

Advanced Materials Research (Volumes 284-286)

Main Theme:

Edited by:

Xiaoming Sang, Pengcheng Wang, Liqun Ai, Yungang Li and Jinglong Bu

Pages:

557-564

Citation:

Y. L. Li et al., "Study on the Mechanical Properties and Creep Behaviour of Carbon Fiber Nano-Composites", Advanced Materials Research, Vols. 284-286, pp. 557-564, 2011

Online since:

July 2011

Export:

Price:

$41.00

[1] M. Cochet, W. K. Maser, A. M. Benito, M. A. Callejas, M. T. Martinez and J. M. Benoit, Synthesis of a new polyaniline/nanotube composite: "in-situ" polymerization and charge transfer through siteselective interaction, Chem. Comm. 16 (2001).

DOI: https://doi.org/10.1039/b104009j

[2] Hayhurst DR. J. Mech. Phys. Solids 1972; 20: 381.

[3] Finnie L, Heller WR. Creep of engineering materials. London: McGraw-Hill Book Company, (1959).

[4] Bendersky L, Rosen A, Mukherjee AK. Int. Metal. Rev. 1985; 130: 1-15.

[5] Mughrabi H. Acta Metall. Mater. 1991; 139: 3067-3070.

[6] S. Kumar, H. Doshi, M. Srinivasarao, J. O. Park and D. A. Schiraldi, Fibers from polypropyle- ne/nano carbon fiber composites, Polymer 43 (2002) 1701–1703.

DOI: https://doi.org/10.1016/s0032-3861(01)00744-3

[7] D. Qian, E. C. Dickey, R. Andrews and T. Rantell, Load transfer and deformation mechanisms in carbon nanotube-polystyrene composites, Applied Physics Letters 76(20) (2000) 2868–2870.

DOI: https://doi.org/10.1063/1.126500

[8] M. T. Kortschot and R. T. Woodhams, Computer Simulation of the Electrical Conductivity of Polymer composite Containing Matallic Fillers, Polymer Composite, Vol. 9, No. 1, February, (1988), pp.60-71.

DOI: https://doi.org/10.1002/pc.750090109

[9] I. Novak., I. Chodak., Investigation of the correlateion between electrical conductiveity and elongateion at break in polyurethane-based adhesives, Synthesis Metal, Vol. 131, (2002), pp.93-98.

[10] Chen, C. H. and Chen, Y. C., The Creep Behavior of Solid filled Rubber Composites, J. Polymer Research, 1(1), 75-83, (1994).

[11] Zhang, S. Y. and Xiang, X. Y., Creep Characterization of a Fiber Reinforced Plastic Material, J. Reinforced Plastic and Composites , 11, 1187-1195, (1992).

DOI: https://doi.org/10.1177/073168449201101009

[12] Gittus J. Creep, viscoelasticity and creep fracture in solids. London: Appl. Sci, (1975).

[13] Keh A. Phil. Mag. 1965; 9: 12.

[14] Meier M, Blum W. Proceedings of the Fifth International Conference for Creep Fracture of Engineering Materials and Structure, Swansea, 28 March-2 April, 1993: 167.

[15] Oehlert A, Atrens A. Acta Metal. Mater. 1994; 31: 1473-1528.