Thermal Conductivity Enhancement of Epoxies by the use of Fillers

To predict the effect of fillers on the thermal conductivity of epoxies, a model has been proposed which consists of a right circular cylinder of epoxy with a hemisphere of a thermally conductive material imbedded in each end. The laws of heat conduction are then applied to this model to obtain a composite thermal conductivity. The effect of packing density of the spheres is considered, then modified, to accommodate the highly nonspherical nature of the filler particle aggregates. A projection is made to show the effect of filler thermal conductivity and filler concentration on the expected thermal conductivity of an epoxy-base composite. A graphical comparison of these two effects is presented.