Uniform particle distribution by a newer method in composite metal of Al/SiC

Abstract

Preparation of composites of metal with ceramic particle reinforced through the casting process is not uniform because of poor wet ability. The major difficulty is to get a uniform distribution of reinforcement especially in higher volume fractions. An innovative method of producing cast composites is tried in present study to overcome this problem we need homogeneity of matrix. The method involves multi axis rotation of liquid aluminum and silicon carbide particulates packed in a steel pipe inside a rotating drum. Up to 65 % volume of the metal (aluminum)is incorporated by SIC by this technique. Physical Properties like hardness, micro hardness, densities and microstructures have been studied. The distribution of particles as well the mechanical properties are better as compared to that of stir cast composites with similar volume fraction of silicon carbide reinforcement. The composite with 65-volume percentage of silicon carbide of particulates showed a Rockwell Hardness value of 67Rb.In few locations the microstructure showed a non-uniform distribution which can be neglected . There were segregation of silicon carbide particles at a particular location and the hardness obtained there was much higher. The particle distribution is a result of the combined influence of random mixing of particles and liquid aluminum and the solidification pattern