2D and 3D visualization of ductile fracture

The in-situ tensile testing of two new model materials which is specially created to capture coalescence, the final stage of the ductile fracture process, was discussed. The first model material consisted of a single sheet containing 10 microns in diameter holes all the way through the sheet which was tested in a scanning electron microscope (SEM) that enables to observe the coalescence in 2D. The second model material consisted of a sheet bonded on both sides by hole free sheets which was tested in an X-ray computed tomography set-up and provided 3D views of the ductile fracture process. The coalescence in the three dimension (3D) case was delayed to higher strains and the failure of the material was controlled by the macroscopic neck. The results show that orientation of the array of holes with respect to the tensile axis has an effect on the failure path and on the modes of coalescence.