Effect of particle shape on thermal conductivity of copper reinforced polymer composites

Thermal conductivity of copper powder filled polyamide composites are investigated experimentally in the range of filler content 0-30% by volume for particle shape of short fibers and 0-60% by volume for particle shapes of plates and spheres. The thermal conductivity of polymer composites is measured by the Hot-Disk method. It is seen that the experimental values for all the copper particle shapes are close to each other at low particle content, phi < 10, as the particles are dispersed in the polyamide matrix and they are not interacting with each other. For particle content greater than 10% by volume, a rapid increase occurs in the thermal conductivity for the copper fibers filled polymer composite. As a result of this study, thermal conductivity of copper filled polyamide composites depends on the thermal conductivity of the filler particles, filler particle shape and size, and the volume fraction and spatial arrangement of the filter particles in the polymer matrix.