Material characterization at high strain rates for optimizing car body structures for crash events

The demand for increased vehicle safety has become a matter of considerable concern of users. The use of high strength steel is beneficial for the realization of a light weight body with enhanced vehicle safety. An optimum combination of body structure and material is highly required and thus an exact evaluation of high strain rate properties of materials has been also demanded. In this report, the methods for testing the high strain rate tensile properties of sheet materials were reviewed and the recent improvements made for our testing machine, one bar method, were presented. In addition, the points that should be taken into accounts in applying the experimental material data at high strain rates to FEM analysis, which is a key tool for an optimization, were discussed.