Effect of SiC Particle Size and Particle Distribution on Microstructure and Mechanical Properties of A359/SiCp Using Powder Metallurgy

The aim of this study is to characterize the microstructure and mechanical properties of aluminum metal matrix composites (MMCs) containing 20 vol% of silicon carbide particles (SiCp) with different particle sizes. The A359/SiCp MMCs sinterted specimens were respectively manufactured from a blended powder and composite powders by a hot press technique. The consolidated composite with the blended powder exhibited a clustered region of reinforcement particles in the matrix, which was due to the influence of the interfacial debonding of the SiCp/matrix during fracture. On the other hand, a homogeneous particle distribution of the composite powders and the SiCp was observed in the sintered specimens after fracture. Homogeneous distribution of the MMCs and SiCp was significantly affected by the method of the preparation or the powder materials. This phenomena was predominant elevation of the mechanical properties in these composites. †(Received January 25, 2013)