X-ray tomography was used to image the crack path in situ and better understand the role of the microstructural features on the crack propagation. Of particular interest was the role of the orientation domains of the lamellar structure of icetemplated samples . Because of the high absorption of X-rays by zirconia, we could not image cracks in zirconia composites. We choose instead to prepare similar composites from ice-templated alumina, the later having a much lower absorption coefficient. Ice-templated alumina samples were prepared with the exact same conditions than these previously described in YSZ, yielding similar microstructure. We developed a simple setup for the tomograph to initiate and propagate a crack in situ in a bent, notched sample (see the radiograph shown in Fig. ). The notched sample is placed between two fixtures, inside a custom compression testing device, described in . The sample is clamped in the fixed lower fixture, while its upper part is in contact with the inclined surface of the upper fixture. A vertical displacement of this inclined surface induces a bending stress on the sample, and thus initiates the propagation of the crack. The crack in the notch area remains at an almost constant position, which facilitates the imaging. Although we cannot precisely estimate the stress level on the sample, this approach let us identify the role of the orientation domains on the crack propagation, for which the exact stress level is not needed.