MATRIX CRACK IMPINGING ON A FRICTIONAL INTERFACE IN UNIDIRECTIONAL BRITTLE MATRIX COMPOSITES

G. P. Tandon, AdTech Systems Research Inc. and N. J. Pagano, Materials Directorate

ABSTRACT

The objective of this work is to study the effect of a frictional interface on the extent of interfacial debonding and internal stress distribution within a unidirectional ceramic matrix composite under thermo-mechanical loading. The configuration considered is a concentric cylinder with an annular crack in the axial plane of the matrix while the fiber-matrix interface is made to obey the Coulomb friction law. The present approach of employing a variational model is shown to satisfy all boundary and inequality conditions in the slip and stick regions and at the slip-stick transition point. The results are also shown to be in very good agreement with a numerical elasticity solution for points away from the matrix crack tip while some of the peculiarities near the crack tip associated with the numerical solution are identified.