Thermal conductivity behavior of SPS consolidated AlN/Al composites for thermal management applications

AlN/Al composites are a potentially new kind of thermal management material for electronic packaging and heat sink applications. The spark plasma sintering (SPS) technique was used for the first time to prepare the AlN/Al composites, and attention was focused on the effects of sintering parameters on the relative density, microstructure and, in particular, thermal conductivity behavior of the composites. The results showed that the relative density and thermal conductivity of the composites increased with increasing sintering temperature and pressure. The composites sintered at 1550°C for 5 min under 70 MPa showed the maximum relative density and thermal conductivity, corresponding to 99% and 97.5 W·m−1·K−1, respectively. However, the thermal conductivity of present AlN/Al composites is still far below the theoretical value. Possible reasons for this deviation were discussed.