Mechanical behaviour of a β-TCP ceramic with a random porosity: Study of the fracture path with X-ray tomography

Macro-porous β Tricalcium Phosphate (β-TCP) samples were produced by a sacrificial template method with polyethylene (PE) beads used as pore formers. X-ray computed tomography was used at two resolutions to characterize the structure at the scale of the sample and at the scale of the microstructure. For the latter scale, the sample was scanned in a so called “local” tomography mode, in which the specimen is placed close to the X-ray source. These images allow observing some details which were not visible at a lower resolution. Then, an ex situ uniaxial compression test was performed and the deformation of the sample was followed at low resolution with the tomograph. The 3D images showed the importance of clusters of macro-pores on the crack initiation and propagation in ceramics with a random porosity.