Untersuchung der Vorhersagegenauigkeit empirischer Modelle zur Beschreibung des Werkstoffverhaltens über große Dehnratenbereiche

FEM simulation to assess formability and crash performance is used increasingly in automobile industry in order to reduce development time of complete new vehicle models and platforms. The simulations give the finite deformation answer to loading conditions typically not only for forming but also for crash conditions. Reliable material data is one input covering description of mechanical behaviour under dynamic loading as well as in certain temperature ranges. Empirical derived models are used to extrapolate material data determined by experiment to ranges of strain, strain rate and temperature needed for the FEM simulations. The potentials and limitations to represent strain rate dependence of flow curves over wide strain rate ranges of selected empirical derived models will be discussed for some typical steel grades in automobiles.