Abstract
High resolution synchrotron microtomography and strain mapping of individual fibres were performed at the ESRF, Grenoble, France. In this manner, the strain distributions along individual fibres have been measured in relation to matrix and fibre cracking for a fatigue cracked Ti/SiC fibre composite specimen. The interfacial shear stress distributions in the bridging fibres were derived from the fibre strains. These indicate how the extent of debonding decreases from the notch towards the crack tip. The debonding behaviour was modelled using a partial debonding shear lag model. Upon unloading the sliding of the debonded regions reversed leading to fretting wear and an associated reduction in interface shear strength near the crack relative to monotonic loading tests.