Observation of Fretting Fatigue Cracks by Micro Computed Tomography with Synchrotron Radiation

In the present study, micro computed tomography (CT) with synchrotron radiation (SR) of SPring-8 was applied to observe and evaluate the fretting fatigue crack propagation in a Ti alloy. The shape of fretting fatigue cracks and crack coalescence could be evaluated quantitatively. The shape of fatigue cracks obtained by SR-CT imaging agreed well with the geometry of fracture surface obtained by the stereogram analysis of scanning electron microscopy. Transition of crack propagation mode inside specimen in fretting fatigue could be observed nondestructively.