Bend-Forming Technology for Ultra High Strength Steel Sheets 2012-01-0532
Ultra high strength steels have contributed to weight reduction in automobiles. However, due to the poor formability of these materials, it is difficult to manufacture automotive parts with complex shapes using conventional sheet metal forming techniques such as deep drawing, bulging, and stretch flange forming.
In this study, a bend-forming technology which enables forming of complex shapes with ultra high strength steel sheets is investigated. The target part was a front side member extension (FSM EXT) of a white body. The part has a dogleg shape and must provide adequate crashworthiness. The basic structure of the FSM EXT produced by this bend-forming technology was proposed. A bend-forming process consisting of three stages was proposed from the standpoint of commercial production. FSM EXT prototypes showed excellent crashworthiness in FEM simulations and crash tests.
This new technology is expected to contribute to wider application of ultra high strength steels to automobile parts with complex shapes.