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Determination of Interfacial Shear Strength in Epoxy/Glass Composites by Multi-Fiber Fragmentation Test (MFFT)



Edward D. McCarthy, Jae H. Kim, N. Alan Heckert, Stefan D. Leigh, Gale A. Holmes, Jeffrey W. Gilman


The mechanical strength of a structural composite is strongly affected by the strength and toughness of the interface achieved between the continuous matrix phase, or resin, and the re-inforcing phase, normally consisting of multiple arrays of carbon or glass fibers. Interfacial shear strength (IFSS) is the accepted parameter for quantifying the strength of the matrix-fiber interface. However, the value of IFSS is not directly accessible by measurement and must be approximated indirectly from other data. One mechanical test which generates such data is the single fiber fragmentation test (SFFT). In this paper we extend the SFFT technique to multiple fiber arrays (multi fiber fragmentation test MFFT) to more closely study the transfer of stress from matrix to reinforcement. We use MFFT data obtained from a conventional epoxy / E-glass system to show that the spatial distribution of fiber breaks along the axes of fibers in close bundles is fitted best by a uniform rather than a Weibull distribution. This knowledge can improve the accuracy of calculations for local and global IFSS in micromechanics specimens.
Proceedings Title
19th International Conference on Composite Materials
Conference Dates
July 28-August 2, 2013
Conference Location
Montreal, CA


epoxy resin, glass fiber, polymer composites, interfacial shear strength, fragmentation


McCarthy, E. , Kim, J. , Heckert, N. , Leigh, S. , Holmes, G. and Gilman, J. (2013), Determination of Interfacial Shear Strength in Epoxy/Glass Composites by Multi-Fiber Fragmentation Test (MFFT), 19th International Conference on Composite Materials, Montreal, CA (Accessed June 14, 2024)


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Created August 1, 2013, Updated October 12, 2021