AL/TIC COMPOSITES PRODUCED BY MELT INFILTRATION

An Al/TiC composite has been developed using a melt infiltration technique. Green performs of TiC were partially sintered to densities ranging from 50 to 85%. They were then infiltrated with molten aluminium in argon at atmospheric pressure, at temperatures ranging from 950 to 1350-degrees-C. The variations in mechanical properties of this composite material with ceramic content and fabrication conditions are presented and the resulting microstructures are discussed. The composite exhibited excellent tensile strength values of approximately 475 MN m-2 and up to 5% elongation. Fracture behaviour mechanisms are also described in relation to the stress-strain curves. High infiltration temperatures were found to be detrimental to the mechanical properties since the TiC particle network, which formed during sintering, was broken down by the metallic phase.