Implementierung und Simulation von lokalen Verstärkungen in Profilbauteilen mit veränderlichem Querschnitt

The development of a vehicle structure is currently dominated by the concept of “light-weighting” driven by both fuel efficiency (Carbon dioxide emissions) and weight/cost reduction. To this end there is a strong desire for the utilization of material mix within the BIW structure (high- and highest strength-steels, aluminum and plastics). The related challenge is forming and joining these different substrates to build the most effective application including the use of reinforcements in critical areas. The local reinforcement based on structural foam systems has become one of the main contenders for the optimization of the classical metal solution. The key driver behind this concept is the improved weight/performance ratio targeting buckling and folding prevention of thin pillar cross sections and profiles resulting in a more enhanced and efficient energy absorption system. Such benefits can directly translate into potential weight savings as the foam is only used in a local pillar area allowing the steel to efficiently sustain the loads and prevent buckling of the section without the need of unnecessary reinforcements or increased thickness. Structural foam reinforcements and their effects can be analyzed effectively by the finite element method. Computer Aided Engineering (CAE) tools virtually allows the optimize use of materials and designs before building costly prototypes. To understand the predictability and accuracy of these simulations a verification and validation of the material model approach is clearly advantageous. In this study a closed section profile with and without structural foam is used to correlate the simulation with the corresponding dynamic 3-point bending test. An example with an in-situ placement of structural foam reinforcement has been extended in the innovative application concept based on a T3-Tube with variable cross sections by ThyssenKrupp Steel targeting a B-pillar profile. A side impact crash study will show the potential of such a T3-Tube combined with the structural foam reinforcement.