Fabrication process and thermal properties of SiCp/Al metal matrix composites for electronic packaging applications

The fabrication process and thermal properties of 50-71 vol% SiCp/Al metal matrix composites (MMCs) for electronic packaging applications have been investigated. The preforms consisted with 50-71 vol% SiC particles were fabricated by the ball milling and pressing method. The SiC particles were mixed with SiO2 as an inorganic binder, and cationic starch as a organic binder in distilled water. The mixtures were consolidated in a mold by pressing and dried in two step process, followed by calcination at 1100 degreesC. The SiCp/Al composites were fabricated by the infiltration of Al melt into SiC preforms using squeeze casting process. The thermal conductivity ranged 120-177 W/mK and coefficient of thermal expansion ranged 6-10 x 10(-6)/K were obtained in 50-71 vol% SiCp/Al MMCs. The thermal conductivity of SiCp/Al composite decreased with increasing volume fraction of SiCp and with increasing the amount of inorganic binder. The coefficient of thermal expansion of SiCp/Al composite decreased with increasing volume fraction of SiCp, while thermal conductivity was insensitive to the amount of inorganic binder. The experimental values of the coefficient of thermal expansion and thermal conductivity were in good agreement with the calculated coefficient of thermal expansion based on Turner's model and the calculated thermal conductivity based on Maxwell's model. (C) 2000 Kluwer Academic Publishers.