Thermal Conductivity of Unidirectional Reinforced Composite Materials—Experimental Measurement as a Function of State of Cure

Abstract

The thermal conductivity of a thermosetting polymeric matrix-based composite material is a thermophysical parameter, which varies significantly during the transformation of the matrix. These variations have a considerable effect on heat transfers within a thick piece in the process and therefore on transformation kinetics of the polymer. In order to address the analysis method used to determine the parameter variations according to both temperature and state of cure of the transformation, the experimental device developed by the authors is first described. Then, the results, experimentally obtained by inverse heat conduction with a composite of Fiberglas^® and epoxy resin, are compared with those given by an effective thermal conductivity model.

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