Search Results

The remarkable evolution of steel technology in recent years has resulted in the development of new High Strength Steels (HSS) that are increasingly used in today's automobiles. The advanced performance of these grades in ductility and rapid hardening characteristics provides an opportunity to stamp complex geometries with in-panel material strengths far exceeding those of conventional high strength grades of steel. This provides an opportunity to improve an automotive body's performance in crash, durability and strength while reducing the overall weight of the vehicle. An improved understanding of the forming characteristics of these advanced HSS and accurate prediction of the material processing strain will allow vehicle designers to fully explore the opportunities of increased yield, strain hardening, formability and strength and the potential this creates to reduce mass and improve the performance of the automotive body.

This paper describes the results of the computational analysis of UltraLight Steel Auto Body (ULSAB) crash simulations that were performed using advanced material modeling techniques. The effects of strain-rate sensitivity on a high strength steel intensive vehicle was analyzed. Frontal and frontal offset crash scenarios were used in a finite element parametric study of the ULSAB body structure. Comparisons are made between the crash results using the piece-wise-linear isotropic plasticity strain-rate dependent material model, and the isotropic plasticity material model based on quasi-static properties. The simulation results show the importance of advanced material modeling techniques for vehicle crash simulations due to strain-rate sensitivity and rapid hardening characteristics of advanced high strength steels.