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Carbon nanotube–copper (CNT/Cu) composites have been successfully synthesized by means of a novel particles-compositing process followed by spark plasma sintering (SPS) technique. The thermal conductivity of the composites was measured by a laser flash technique and theoretical analyzed using an effective medium approach. The experimental results showed that the thermal conductivity unusually decreased after the incorporation of CNTs. Theoretical analyses revealed that the interfacial thermal resistance between the CNTs and the Cu matrix plays a crucial role in determining the thermal conductivity of bulk composites, and only small interfacial thermal resistance can induce a significant degradation in thermal conductivity for CNT/Cu composites. The influence of sintering condition on the thermal conductivity depended on the combined effects of multiple factors, i.e. porosity, CNTs distribution and CNT kinks or twists. The composites sintered at 600°C for 5 min under 50 MPa showed the maximum thermal conductivity. CNT/Cu composites are considered to be a promising material for thermal management applications. [ABSTRACT FROM AUTHOR]

The thermal conductivity of SiCp/Al composites with high volume fractions of 46 to 68% has been investigated. The composites were fabricated by pressureless infiltrating liquid aluminum into SiC preforms with monomodal and bimodal size distributions. The density measurement indicates that a small amount of pores is presented for the composites approaching their maximum volume fractions. An analytical model with an explicit expression is proposed for describing the thermal conductive behavior of the composites with multimodal-reinforced mixtures in terms of an effective medium approach taking into account the porosity effect. Predictions of the developed effective medium expression reveal good correspondence with the experimental results, and explore how each of the considered factors (i.e., particle size ratio, volume fraction ratio, and porosity) can have a significant effect on the thermal conductivity of the composites with bimodal mixtures. [ABSTRACT FROM AUTHOR]