Synthesis of Al/SiC based functionally gradient materials using technique of gradient slurry disintegration and deposition: Effect of stirring speed

Abstract

In the present study, Al/SiC based functionally gradient materials (FGMs) were successfully synthesised using the gradient slurry disintegration and deposition technique. Gradients of SiC for the starting weight of 18% were successfully established by varying the stirring speed of the molten melt. The results revealed, in general, increases in the weight percentage and clustering tendency of SiC, porosity, and microhardness and a reduction in grain size, with increasing distance from the base of the FGM ingots. The results also showed that an increase in the stirring speed increases the homogeneity of SiC particulates distribution, thus resulting in a decrease in the gradient of reinforcement along the deposition direction. Furthermore, an increase in the stirring speed decreases the number of clusters formed per unit area. An attempt has been made in the present work to establish the trend between processing parameters, such as stirring speed and the gradient of SiC particulates realised in the ingots. © 2002 IoM Communications Ltd.