Biaxial Specimens for the Analysis of Ductile Damage and Fracture in Sheet Metals

The paper discusses geometries for flat specimens which can be used in an experimental program under biaxial loading conditions. Corresponding to the well-known X0- and H-specimens, geometries of new specimens taken from very thin sheet metal are proposed. Instead of notches in thickness direction as used for the design of the X0- and H-specimen, arrangement of holes is used for localization of inelastic deformations and damage in required regions of the samples. Load–displacement curves, principal strain fields on the surfaces of critical parts of the specimens and photos from the fracture surfaces taken by scanning electron microscopy are shown. These results from experiments with biaxially loaded specimens clearly demonstrate the efficiency of the new specimens.