A Novel Geometry for Shear Test Using Axial Tensile Setup

This paper studies a novel geometry for the in-plane shear test performed with an axial
electromechanical testing machine. In order to investigate the influence of the triaxiality rate on the
mechanical behavior, different tests will be performed on the studied material: simple tensile tests,
large tensile tests and shear tests. For the whole campaign, a common equipment should be
employed to minimize the impact of the testing device. As a consequence, for the shear tests, the
geometry of the specimen must be carefully designed in order to adapt the force value and make it
comparable to the one obtained for the tensile tests. Like most of the existing shear-included tensile
test specimens, the axial loading is converted to shear loading at a particular region through the
effect of geometry. A symmetric shape is generally preferred, since it can restrict the in-plane
rotation of the shear section, keep shear increasing in a more monotonic path and double the force
level thanks to the two shear zones. Due to the specific experimental conditions, such as dimensions
of the furnace and the clamping system, the position of the extensometer or the restriction of sheet
thickness (related to the further studies of size effect at mesoscale and hot temperature), several
geometries were brought up and evaluated in an iterative procedure via finite element simulations.
Both the numerical and experimental results reveal that the final geometry ensures some
advantages. For instance, a relatively low triaxiality in the shear zone, limited in-plane rotation and
no necking are observed. Moreover, it also prevents any out-of-plane displacement of the specimen
which seems to be highly sensitive to the geometry, and presents a very limited influence of the
material and the thickness.