| In the last two decades, Metal Matrix Composites have brought forth attractive properties such as high hardness, increased elastic stiffness and yield strength, good wear and abrasion resistance and high temperature creep resistance. Many of the MMCs produced today, however, do not exhibit the ideal properties that would be anticipated based on the rule of mixture calculations. This behaviour has been attributed to reinforcement degradation and poor matrix-to-reinforcement bonding.The present study addresses the issue of interface behaviour in the SiC particulates in an aluminum matrix system. The wettability over time as a function of ceramic oxidation and magnesium addition have shown that: (1) aluminum tends to wet silicon carbide to a greater degree with the presence of a thin oxidation layer of silica, and (2) magnesium added to the aluminum melt, in one and three mass-percent quantities, significantly improves its wetting on silicon carbide. |
