MICROMODELLING OF EFFECTIVE STRESS INTENSITIES FOR BRIDGED CRACKS IN FIBER-REINFORCED TITANIUM METAL-MATRIX COMPOSITES

Weight function methods have been used to model and assess the crack growth resistance of fibre-reinforced composite materials. Many trends in observed crack growth resistance behaviour in the presence of crack bridging can be predicted accurately. For the case of single dominant cracks the application of fracture mechanics parameters to characterize crack growth appears to be appropriate. In particular the model can predict accurately crack growth rates in near crack arrest regions, together with the onset of crack arrest. Effects of unbridged crack length, volume fraction of fibres and fibre failure on crack growth rates have all been predicted.