Microstructures and thermal properties of A356/SiCp composites fabricated by liquid pressing method

A356/45vol.% SiCp composites with a uniform distribution of SiC particles have been fabricated by a liquid pressing method. Increasing the melt temperature, holding time and pre-treatment of SiCp by thermal oxidation improves the soundness of composites for the liquid pressing method. The sound composites exhibited low coefficient of thermal expansion (8 ppm/K) and high thermal conductivity (155 W/m K). The measured values for coefficient of thermal expansion agree well with the predicted values based on Turner's model irrespective of porosity. The measured values for thermal conductivity decrease with porosity, and the effect of pore on the thermal conductivity has been evaluated based on the modified Hasselman-Johnson model. (C) 2012 Elsevier Ltd. All rights reserved.