Thermal conductivity of diamond particle dispersed aluminum matrix composites fabricated in solid–liquid co-existent state by SPS

Abstract

Diamond particle dispersed aluminum (Al) matrix composites were fabricated in solid–liquid coexistent state from the powder mixture of diamond, pure Al and 5056-type Al–Mg alloy by spark plasma sintering (SPS) process. Microstructures and thermal conductivities of the composites fabricated were examined. These composites can be well consolidated at 813K for 0.6ks and scanning electron microscopy detects no reaction at the interface between the diamond particle and the Al matrix. The relative packing density of the diamond-Al composite fabricated was 97% or higher in a volume fraction range of diamond between 25.5 and 45.5%. The thermal conductivity of the Al matrix composite containing 45.5vol.% diamond reached 403W/mK, approximately 76% the theoretical thermal conductivity estimated by Maxwell–Eucken’s equation.