Computational study of crack growth in SiC/Al composites

An elastic-plastic finite-element analysis has been carried out to study the fracture behaviour of a SiC/6061-Al filamentary composite. The composite was modelled as a two-material cylinder subjected to uniform displacement and consisting of an inner cylinder simulating the fibre and a surrounding shell simulating the matrix. Using the strain energy density criterion, the critical applied displacements for crack initiation and stable crack growth were determined for three studied cases: an intact fibre, a cracked fibre, and a fully broken fibre. The numerical results were compared, where possible, to experimentally obtained ones. Finally, results concerning the variation of strain energy density versus distance from the crack tip, for the determination of the critical value of applied displacement at crack initiation, are presented and discussed.