Comparisons of thermal conductive behaviors of epoxy resin in unidirectional composite materials

This paper reports thermal conductive behaviors of three kinds of materials, i.e., epoxy resin bar, carbon fiber bundles/epoxy system, and unidirectional carbon fiber/epoxy lamina along 0A degrees and 90A degrees directions. The apparatus for thermal conduction measurement was manufactured and calibrated with an aluminum bar with known thermal conductivity. The thermal conductive behaviors, including the thermal conductive rate and thermal equilibrium time, were tested and numerically simulated with finite element method. It is found that these materials have similar thermal conductive characteristics with same trends of temperature-time curves and thermal gradient-time curves. In addition, with the increase in fiber volume content or decrease in fiber orientation angle, the thermal conductive rate will be speeded up and thermal equilibrium time will be reduced. The temperature of epoxy resin in composite will increase with the increment of fiber volume content. Due to the existence of interface between fiber and resin, the overall thermal conductive ability of composite will be weakened. Owing to the epoxy resin, carbon fiber bundles/epoxy system and unidirectional carbon fiber/epoxy lamina are the basic materials for the laminates or complex preform reinforced composites, and the thermal conductive behaviors of these basic materials could be extended to design the thermal conductive behaviors of laminates and complex reinforcement composite materials.