Abstract
Orthotropic materials show different thermo-elastic constants depending on their fibre orientation. While most materials undergo a positive elongation with increasing temperature, carbon fibres present a heat-shrink behaviour, which in carbon fibre composites has an important consequence on thermoelastic constants. A decrease in thermoelastic constant with frequency has already been observed in glass fibre composites. Experiments made on uniaxial carbon fibre composites showed that the longitudinal thermoelastic constant increases with the frequency, while the transverse constant decreases. Furthermore, due to the opposite signs of the thermoelastic carbon fibre constant and of the surrounding resin matrix, the absolute values of the longitudinal thermoelastic constant were ten times lower in CFRPs than in GFRPs. An analytical model could successfully reproduce the frequency dependence of the longitudinal thermoelastic constant, thus helping to explain the reason for the observed behaviour. Two calibration samples were used to obtain the thermoelastic constants in the longitudinal and transverse directions. The values of the thermoelastic constants were then applied to a test sample with fibres forming an angle of 10° to the load direction. The expected theoretical results were compared with the results experimentally obtained, showing good agreement. A preliminary calibration of the longitudinal and transverse thermoelastic constants proved to be a useful approach to obtaining the correct value of the thermoelastic constant in a generic direction.
Similar content being viewed by others
References
Salerno A, Desiderati S (2004) Procedure proposal for the correction of nonadiabatic thermoelastic stress analysis results. Rev Sci Instrum 75(2):507–514
Crump DA, Dulieu-Barton JM (2012) Assessment of non-adiabatic behaviour in thermoelastic stress analysis of composite sandwich. Exp Mech 52(7):829–842
Emery TR, Dulieu-Barton JM, Earl JS, Cunningham PR (2008) A generalised approach to the calibration of orthotropic materials for thermoelastic stress analysis. Compos Sci Technol 68(3–4):743–752
Thomson W (1853) On the dynamic theory of heat. Trans R Soc Edinb 20:261–288
Darken L, Gurry R (1953) Physical Chemistry of Metals. McGraw-Hill, London
Wong AK, Jones R, Sparrow JG (1987) Thermoelastic constant or thermoelastic parameter? J Phys Chem Solid 48(8):749–753
Wong AK (1991) A non-adiabatic thermoelastic theory for composite laminates. J Phys Chem Solid 52(3):483–494
Stanley P, Chan WK (1988) The application of thermoelastic stress analysis techniques to composite materials. J Strain Anal 23(3):137–143
Salerno A, Costa A, Fantoni G (2009) Calibration of thermoelastic constants for quantitative thermoelastic stress analysis on composites. Rev Sci Instrum 80:034904
Pitarresi G, Galietti U (2010) A quantitative analysis of the thermoelastic effect in CFRP composite materials. Strain 46:446–459
Zhang D, Enke NF, Sandor BI (1990) Thermographic stress analysis of composite materials. Exp Mech 30:68–73
Wong AK, Sparrow JG, Dunn SA (1988) On the revised theory of the thermoelastic effect. J Phys Chem Solid 49(4):395–400
Salerno A, Costa A (2010) Quantitative thermoelastic measurement on a helicopter glass fiber component underneath a surface antifretting coating, Proc. 14th Intern. Conference on Experimental Mechanics ICEM14, 4-9 July 2010. Poitiers, France, EPJ Web of Conferences 6, 38006 ISBN 978-2-7598-0565-5; pp. 38006-p1 38006-p8 on CD. doi:10.1051/epjconf/20100638006
Acknowledgments
The authors wish to thank Agusta-Westland for the support given for the present research.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Costa, A., Salerno, A. Investigation on the Thermoelastic Constant of Carbon Fibre Composites. Exp Mech 53, 1597–1605 (2013). https://doi.org/10.1007/s11340-013-9772-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11340-013-9772-z