a simplified description of the uniaxial tensile test used for calibrating constitutive models of orthotropic porous sheet metals

In the present work, a simplified model of the uniaxial tensile test is developed for orthotropic metallic sheets. this model is mainly established for tensile test analysis and calibration of material parameters. the constitutive equations included in the model are based on an anisotropic gurson-tvergaard-needleman model combined with the hill 1948 quadratic yield criterion. at first, a detailed description of the constitutive equations along with their computer implementation is presented. then, by comparing the force and void evolution diagrams predicted by the model with numerical and experimental results the efficiency and accuracy of the model are assessed. finally, the effect of different parameters on the traction force and evolution of voids during uniaxial tensile tests are studied. the material parameters used in the calibration procedure are as follows: initial void volume fraction, two adjusting parameters, nucleation of void volume fraction, standard deviation, mean value of void nucleation strain, and sample orientation with respect to the rolling direction. the tests performed by the authors prove the capability of the simplified model to describe accurately the mechanical response of orthotropic sheet metals.