Effect of Particle Morphology on Thermal Properties of TiB2 Particle Dispersed Pure Aluminum Composites

Abstract

Particle size and distribution affect the thermal properties such as thermal conductivity, thermal expansion, and mechanical properties. In this study, TiB2 particles were used for the dispersant of pure aluminum composites because of high thermal conductivity and low thermal expansion of TiB2. Composites with different dispersibility and volume fraction of particles were prepared by spark plasma sintering. The effect of particle dispersibility in composites on thermal conductivity was estimated quantitatively by the simulation and experiments. As increasing dispersibility, the thermal conductivity was decreased and Vickers's hardness increased, but alternation for thermal conductivity was very small. With increasing volume fraction of particles, the effect of the particle dispersion on the change of the thermal conductivity increased. In addition, the empirical equation of the thermal conductivity considering dispersibility was estimated. The coefficient of thermal expansion decreased with increasing the particle volume fraction, and the experimental value quite accorded with a result provided by the rule of mixture.