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A Test Method for Determining the Fiber and Void Contents of Carbon/Glass Hybrid Composites



Walter G. McDonough, Donald L. Hunston, Joy P. Dunkers, Kathleen M. Flynn


Hybrid composites are increasingly being used in infrastructure, oil recovery, and aerospace applications. These hybrids use two different fibers to reinforce the resin, thereby gaining some of the advantageous properties of both fibers. Typically carbon and glass are used since this combination provides high performance and low cost. Critical issues in such materials are the fiber mix ratio and the fiber and void contents. At present, there is no simple way to determine these features although many techniques exist for measuring the components in single reinforcement composites. Our recent work has shown how this information can be obtained and as a result, we will be proposing an extension of the burn off test in ASTM D 3171-99 to characterize carbon/glass hybrids. We present data from tests on a series of samples made with known compositions and data on a commercially prepared sample where fiber mix ratio is known and void content was determined by using microscopy.
Journal of ASTM International


burnout test, carbon fibers, glass fibers, hybrid composites


McDonough, W. , Hunston, D. , Dunkers, J. and Flynn, K. (2004), A Test Method for Determining the Fiber and Void Contents of Carbon/Glass Hybrid Composites, Journal of ASTM International, [online], (Accessed June 17, 2024)


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Created March 1, 2004, Updated February 19, 2017