Development of a New Method for Strain Field Optimized Material Characterization

Due to technical progress, cars of the future will consist of even more different materials than they already do today. Especially plastic materials will experience a further increase of importance, as they provide advantages such as a low density and the freedom to shape them unconventionally. In view of this trend, it is essential to improve the quality of predictions derived from corresponding simulations. Modelling the material in an appropriate way is crucial when simulating a component. While in case of metals plastic deformation happens at a constant volume and therefore is easy to describe, this kind of incompressibility does not apply to plastics. Furthermore, the hardening behavior of these materials is usually significantly more complicated. Therefore, complex mechanical descriptions have to be used for the simulation of plastics, which describe hardening and failure in a multiaxial state of stress. Although those models have been available for some time, it is still cumbersome to calibrate their parameters. In particular, the correct prediction of the strain field, which is the key to characterize material failure e.g. with GISSMO [5], is challenging, as a large number of degrees of freedom have to be adjusted simultaneously.