Fracture behaviour and pullout analysis in ceramic matrix composites using m0dified Rosen's model

Abstract

A modified Rosen's model is proposed to predict the ultimate tensile load and pullout in ceramic matrix composite materials. The model assumes a Weibull distribution for the fibre strength and that the matrix is already cracked. The solid is discretised in fibre segments between matrix cracks. After fracture of one fibre segment, the load is redistributed among the intact neighbouring segments. This in turn produces further fibre failures and subsequent load transfer. Then, the load is increased on the testpiece until new segments are fractured, and the procedure is iterated until one fracture path isfound. The model is applied to a silicon carbide fibre/calcium aluminium silicate (SiC_f/CAS) material and compared with experimental results. It is concluded that upper and lower bounds can be obtained using different load transfer assumptions.