Thermal Conductivity of Particulate Epoxy Matrix Composite Materials

The thermal conductivity was tested for epoxy-based composites filled with microparticles of silicon carbide and fly ash with different volume fractions and different particle sizes. Three volume fractions of the fillers (10, 20, and 30 Volume%) and five sizes of particles (37, 53, 75, 106, and 150 microns). The silicon carbide particles and fly ash were fabricated separately by using the hand lay-up method. Using Lee's disc apparatus, the thermal conductivity of all samples was measured experimentally. According to the results, the thermal conductivity of epoxy composites rises with increases in the volume percentage of silicon carbide particles. Same behavior is found as decreasing particle size of these particles. The maximum thermal conductivity values were found, which were 40.6% higher than the thermal conductivity value of pure epoxy. In contrast, the thermal conductivity of the epoxy composites falls as the volume fraction increases when adding the fly ash. Same behavior is found as decreasing particle size of the fly ash. The lowest thermal conductivity value was obtained with a reduction rate of 32.5% of the thermal conductivity of pure epoxy. In conclusion, adding fly ash to pure epoxy improves the thermal insulation properties of the fly ash/epoxy composites.