STUDY OF PARTICLE DISTRIBUTION IN AL-SIC PARTICULATE COMPOSITE BY RANDOM MOTION OF MOULD

摘要

Synthesis of Al metal matrix composites (MMCs) with ceramic particulate reinforcements via the casting route is associated with the problem of non-uniform distribution of particulate. The problem of non-uniform distribution is more for the case of larger particulate volume fraction. In the present study a novel method has been tried to overcome this. It involves random movement of mold containing liquid aluminium and ceramic particulates ie SiC. In the present study a spherical mold containing molten aluminium and SiC particulates of size 50-100μm is allowed to rotate in a cylindrical drum to impart a random rotation as well translation Before the design of the experiment at work the process simulation has already been completed. Accordingly the process has been fabricated. At present the process is a crude but preliminary experiments have shown that the distribution of particles obtained by this technique are better as compared to that of stir cast composites with similar volume fraction of reinforcement. However, the results obtained by the novel technique varied as proper control over the random motion of the mold were not possible. Although uniform microstructure could be obtained in most of the experiments in some cases and certain zones the microstructure showed a non uniform distribution of particles. The temperature of mold before it is subjected to random movement strongly influenced the particle distribution.