Abstract
Tensile stress is necessary for observing fatigue cracks by X-ray computed tomography (CT) because the fatigue crack tip is normally closing without fatigue loading. In this study, the influence of the tensile stress on the observing results of a fatigue crack by micro CT with synchrotron radiation was investigated. The area of the fatigue crack projected in the specimen axial direction has not changed with the increase in the tensile stress, though the opening displacement of the crack on the surface increased with the increase in the tensile stress.
