Application of austenitic steels in energy absorbing structures

Occupants protection during vehicle crash is one of the major problems considered at vehicle designing stage. The increasing safety as well as comfort requirements results in the total vehicle weight increase. On the other hand, higher mass influence on the fuel economy of vehicle. Thus, it is very important to maintain or even reduce vehicle weight. One of the solutions of this problem is application of a new materials having good strength-to-weight ratio i.e. high strength steels (HSS). They are often used in protective and energy absorbing structures in automotive industry. One of HSS so-called austenitic steels are characterized by excellent mechanical properties such as: high strength, strong strain, and strain rate hardening. Those mechanical effects are consequence of microstructural evolution during strong deformations i.e. twinning and phase transformation. As a consequence those steels are very good material for the purposes of energy absorbing and protective structures. This article presents the results of mechanical properties tests of VP159 austenitic steel. On the basis of experimental data, the JC constitutive model has been calibrated. The obtained results were used for the computer simulations of energy absorbing of square profiles made of analysed material. The results were compared with other types of steel.