Effect of Interfacial Coatings on Thermal Conductivity of Diamond/Al Composites

Abstract

In this paper, the acoustic mismatch model and the differential effective medium scheme were applied to predict the influence of different interfacial coatings (Si and SiC) on the interfacial thermal conductivity and thermal conductivity of the Diamond/Al composites, respectively. With the increase of the thickness of interfacial coatings, the interfacial thermal conductivity and of the thermal conductivity of Diamond/Al composites decreased. In order to obtain ideal thermal conductivity of Diamond/Al composites, the thickness of the coating should be controlled below 1 μm. When the volume fraction of diamond was 60% and the average particle size was 100 μm, the interfacial thermal conductivity of Si and SiC coated Diamond/Al composites were in the range of 1.77×107∼1.1×108 W/(m2 · K) and 2.44×107∼1.29×108 W/(m2 · K), respectively; the thermal conductivity of Si and SiC coated Diamond/Al composites were in the range of 541.58∼764.15 W/(m· K) and 594.45∼777.3 W/(m· K), respectively. The thermal conductivity of Si and SiC coated Diamond/Al composites increased with the volume fraction and average particle size of Diamond, and the thermal conductivity of SiC coated Diamond/Al composites was higher than that of Si coated composites. SiC interface coating was proposed to be the most promising candidates to improve the thermal performance of Diamond/Al composites.