SiC/Al composites with a high volume fraction of SiC were prepared at 1,150 oC by pressureless infiltration. The volume fraction of SiC was increased by decreasing the amount of starch in the green body. Both the microstructure and the strength of the composites were investigated. The results showed that the strength decreased with an increase of the particle size and volume fraction of SiC. It is suggested that the interface between the SiC particles, which were not sintered, are the cause of defects in the composites. The defects led to a decrease of the strength with an increase of the volume fraction of SiC.

Keywords: SiC/Al composite, Pressureless infiltration, Volume fraction, Strength.