Fracture toughness and fiber bridging of carbon fiber reinforced carbon composites

Abstract

A fracture mechanics study is reported for two different types of carbon fiber reinforced carbon matrix composites, a short-fiber felt composite and a satin weave laminated-composite. It is emphasized prior to discussing their fracture mechanisms that the first matrix cracking is the most important fracture process in these C/C composites. Fiber pull-out and bridging processes in the wake of the propagating crack tip are discussed in relation to experimental R curves. The bridging tractions are estimated by the Dugdale model, from which the fiber bridging-enhanced toughening in lamina composites is demonstrated.