Analysis of damage in metallic materials by X-ray tomography

In situ tensile test coupled with X-ray tomography is a powerful tool for 3D reconstruction and non destructive observation of microstructure and damage of materials, in particular for the comprehension of nucleation, growth and coalescence of voids in metal alloys. A set of tests has been carried out on dualphase steels but also ferrite and martensite. These tests were carried out in order to compare the performance of the dual phase material with a good knowledge of the behaviour of its two constituents separately. Qualitative analysis of the damage events was carried out at many deformation steps, on a same 3D region in the reconstructed volumes. This technique allows a deep insight into the material behaviour and provides experimental support to damage analysis, previously carried out by SEM and optical microscopy. The 3D reconstruction also provides the opportunity for building an accurate geometry for FE analysis.