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Measurement and modeling of internal stresses at microscopic and mesoscopic levels using micro-Raman spectroscopy and X-ray diffraction

Published online by Cambridge University Press:  01 March 2012

B. Benedikt ,
M. Lewis  and
P. Rangaswamy
B. Benedikt
Affiliation:
Engineering Sciences and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
M. Lewis
Affiliation:
Engineering Sciences and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
P. Rangaswamy
Affiliation:
Engineering Sciences and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
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Abstract

In this study, we use X-ray diffraction (XRD) and micro-Raman spectroscopy (MRS) to measure internal strains in sensors embedded in polymer matrix composites. Two types of strain sensors embedded in either chopped graphite fiber∕epoxy matrix composite (MRS) or unidirectional graphite fiber∕polyimide matrix composite (XRD) were investigated. For XRD measurements, the sensors were in the form of spherical aluminum inclusions with diameters ranging from 1 to 20 μm. Due to large cross section area of an incident X-ray beam, only average stresses are reported using the XRD approach. Complementary to XRD experiments, MRS was pursued to measure internal strains in Kevlar-49 fibers embedded in chopped graphite fiber∕epoxy matrix composite. In recent years, MRS as an experimental tool for microstrain measurements has drawn considerable attention mostly due to its excellent spatial resolution. The resolution of MRS typically ranges between 1 and 10 μm, which means that strains can be measured in individual sensors. The principle of this method relies on a change of certain molecular vibration frequencies as a result of an applied stress. Several examples are presented and discussed to demonstrate the potential of combining micro and macrostrain measurements and modeling to capture the stress distribution in heterogeneous materials.

Type
X-Ray Diffraction
Information
Powder Diffraction , Volume 21 , Issue 2 , June 2006 , pp. 118 - 121
Copyright
Copyright © Cambridge University Press 2006

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References

Benedikt, B., Predecki, P., Kumosa, L., Armentrout, D., Sutter, J. K., and Kumosa, M. (2001a). “The Use of X-ray Diffraction Measurements to Determine the Effect of Bending Loads on Internal Stresses in Aluminium Inclusions Embedded in a Unidirectional Graphite Fibre∕PMR-15 Composite,” Compos. Sci. Technol. CSTCEH 61, 1995–2006.Google Scholar
Benedikt, B., Kumosa, M., Predecki, P. K., Kumosa, L., Castelli, M. G., and Sutter, J. K. (2001b). “An Analysis of Residual Thermal Stresses in a Unidirectional Graphite∕PMR-15 Composite Based on the X-ray Diffraction Measurements,” Compos. Sci. Technol. CSTCEH 61, 1977–1994.Google Scholar
Benedikt, B., Rupnowski, P., Kumosa, L., Sutter, J. K., Predecki, P. K., and Kumosa, M. (2002). “Determination of Interlaminar Residual Thermal Stresses in a Woven 8HS graphite∕PMR-15 Composite Using X-ray Diffraction Measurements,” Mech. Adv. Mater. Struct. 9, 375–394.Google Scholar
Benedikt, B., Kumosa, M., and Predecki, P. (2005a). “An Evaluation of Residual Stresses in Graphite∕PMR-15 Composites by X-ray Diffraction,” Acta Mater. ACMAFD 53, 4531–4543.CrossRefGoogle Scholar
Benedikt, B., Lewis, M., and Rangaswamy, P. (2005b). “An Analysis of Internal Strains in Unidirectional and Chopped Graphite Fibre Composites Based on X-ray Diffraction and Micro Raman Spectroscopy Measurements,” Computational Methods and Experiments in Materials Characterisation II (WIT Press, Southampton), pp. 13–22.Google Scholar
Benedikt, B., Lewis, M., and Rangaswamy, P. (2006). “On Elastic Interactions between Spherical Inclusions by the Equivalent Inclusion Method,” Comput. Mater. Sci. CSTCEH in press.Google Scholar
Eshelby, J. D. (1957). “The Determination of the Elastic Field of an Ellipsoidal inclusion, and Related Problems,” Proc. R. Soc. London, Ser. A PRLAAZ 241, 376–396.Google Scholar
Galiotis, C. (1991). “Interfacial Studies on Model Composites by Laser Raman Spectroscopy,” Compos. Sci. Technol. CSTCEH 10.1016/0266-3538(91)90015-H 42, 125–150.Google Scholar
Mori, T. and Tanaka, K. (1973). “Average Stress in Matrix and Average Elastic Energy of Materials with Misfitting Inclusions,” Acta Metall. ADCAAX 21, 571.Google Scholar
Noyan, I. C. and Cohen, J. B. (1987). Residual Stress. Measurement by Diffraction and Interpretation (Springer, New York).Google Scholar
Predecki, P. and Barrett, C. (1979). “Stress Measurement in Graphite∕Epoxy Composites by X-ray Diffraction from Fillers,” J. Compos. Mater. JCOMBI 13, 61–71.CrossRefGoogle Scholar