2014 Volume 50 Issue 12 Pages 428-434
It is known that interfacial debonding between the fiber and matrix is a major mechanism regarding toughness improvement of ceramic matrix composites（CMC）. In this study, a new finite element（FE） model considering fiber/matrix debonding of CMC was proposed. In this model, equality of nodal displacements at the interface and equilibrium of contact forces are assumed as contact conditions.As an advantage, the numerical solutions can be obtained by only one calculation without iterative algorism, which has been performed in contact problems. The present model was formulated for the cases that（ⅰ）Coulomb friction occurs as an nterfacial frictional force, and（ⅱ）a constant nterfacial shear stress works. The obtained numerical results were compared with the theoretical interfacial debonding models. Results show that the numerical results in fiber and matrix stress distributions agree well with those of the theoretical models Furthermore, we deled the formulation of cohesive element（one of finite elements simulating interfacial amage）by assuming a proportional relation between the contact force and relative displacement at the interface. The obtained results edicted qualitatively actual behavior in the fiber and matrix stress distributions at the debonding region.
