This thesis presents a sensitivity analysis of the mechanical response of heterogeneous specimens to variations in the initial material parameters describing the plastic anisotropy of sheet metals. The sensitivity analysis was performed for experimentally determined Lankford coefficients and flow stresses, which were numerically converted in Mathematica into the parameters of the advanced constitutive model YLD2000-2d. These parameters were then implemented into the Abaqus/CAE software via a user-defined material model (UMAT), where numerical simulations of the mechanical response of heterogeneous specimens with different geometries were carried out. For each initial parameter, a 1% variation was applied, followed by a comparison of the internal energy evolution with a reference simulation. The results show that uniaxial tests enable a clearer identification of the most influential initial parameters, while biaxial tests provide a broader insight into their interrelationships. The thesis offers guidelines for selecting optimal specimen geometries and planning experimental procedures for the reliable determination of plastic anisotropy parameters.
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