Interfaces in Ceramic Matrix Composites Following High Temperature Deformation

The role of whisker interfaces during high temperature deformation of ceramic matrix composites has been studied. The effect of the whiskers depends on the actual CMC system used and in particular on the presence or absence of an intergranular amorphous phase. SiCw/Si3N4 and SiCw/Al2O3 have been creep tested at elevated temperatures and reasons for the difference in creep behaviour of the two composites are discussed. It is concluded that the effect of the whiskers upon the high temperature properties of the CMC material is strongly dependent upon the microstructure and properties of the matrix.