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The Electrical and Thermal Conductivity of Woven Pristine and Intercalated Graphite Fiber-Polymer CompositesA series of woven fabric laminar composite plates and narrow strips were fabricated from a variety of pitch-based pristine and bromine intercalated graphite fibers in an attempt to determine the influence of the weave on the electrical and thermal conduction. It was found generally that these materials can be treated as if they are homogeneous plates. The rule of mixtures describes the resistivity of the composite fairly well if it is realized that only the component of the fibers normal to the equipotential surface will conduct current. When the composite is narrow with respect to the fiber weave, however, there is a marked angular dependence of the resistance which was well modeled by assuming that the current follows only along the fibers (and not across them in a transverse direction), and that the contact resistance among the fibers in the composite is negligible. The thermal conductivity of composites made from less conductive fibers more closely followed the rule of mixtures than that of the high conductivity fibers, though this is thought to be an artifact of the measurement technique. Electrical and thermal anisotropy could be induced in a particular region of the structure by weaving together high and low conductivity fibers in different directions, though this must be done throughout all of the layers of the structure as interlaminar conduction precludes having only the top layer carry the anisotropy. The anisotropy in the thermal conductivity is considerably less than either that predicted by the rule of mixtures or the electrical resistivity.
Document ID
Document Type
Preprint (Draft being sent to journal)
Gaier, James R.
(NASA Glenn Research Center Cleveland, OH, United States)
Vandenburg, Yvonne Yoder
(Manchester Coll. North Manchester, IN, United States)
Berkebile, Steven
(Manchester Coll. North Manchester, IN, United States)
Stueben, Heather
(Manchester Coll. North Manchester, IN, United States)
Balagadde, Frederick
(Manchester Coll. North Manchester, IN, United States)
Date Acquired
September 7, 2013
Publication Date
January 1, 2002
Subject Category
Composite Materials
Report/Patent Number
Funding Number(s)
Distribution Limits
Public Use Permitted.
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