THE MECHANICAL-PROPERTIES OF CERAMIC COMPOSITES PRODUCED BY MELT OXIDATION

The strength and fracture toughness of a range of DMOX materials, with and without SiC particulates, have been measured. The strength has been shown to correlate with the SiC particulate size and to be consistent with a model based on the expansion misfit between the particulates and the matrix. The toughness has contributions for both the residual alloy and the SiC. The former has been shown to conform well with the expectations of models based on plastic dissipation in the alloy. The influence of the SiC is found to be strongly dependent on the particulate size and is qualitatively consistent with a contribution to toughness from frictional dissipation at debonded SiC/Al2O3 interfaces.