Shrinkage and densification of particulate reinforced ceramic matrix composites

A model is described for the densification of particulate reinforced ceramic matrix composites when the degree of shrinkage is large. A rule of mixtures model can be used to describe the degree of densification in cases where there is no interfacial reaction between the reinforcement and the matrix. The model is illustrated by reaction sintering of sialon with titanium nitride and also by sintering of clay containing silicon carbide. The extent of linear shrinkage and also the rate of densification decreased with increasing volume fraction of reinforcement phase and these effects are explained on the basis of the model. The correspondence between the data and the model allows the prediction of shrinkage in composite systems where there is no interfacial reaction during the densification process.