Three-dimensional morphology of cementite in steel studied by X-ray phase-contrast tomography

We show that non-destructive, in-line X-ray phase-contrast tomography (PCT) can be used to study the three-dimensional morphology of individual cementite particles in steel with a spatial resolution of approximately 1.5 μm in a sample volume of 600 × 400 × 250 μm3. The smallest detectable cementite grains are 5 μm in size. The PCT results correspond very well to optical microscopy in combination with serial sectioning. We estimate the temporal resolution of PCT for in situ studies of cementite to be 30 min.