Abstract
High strength steels have been applied to the automobile body as a means to reduce weight and improve crash safety performance. In order to satisfy press formability and part performance, improvement of material properties was required. Studies of press forming and crash performance showed the lambda value, or hole expansion ratio, to be especially important for improving formability and part performance. Application to body components, that could not achieved with conventional steels, was realized by the development of the new high strength steel sheet with high elongation and high local ductility
