AHSS: A COMPARISON OF THE MECHANICAL BEHAVIOR OF AN AUTOMOBILE FLOOR CROSSBAR DURING SHEET METAL FORMING

Abstract

One of the fundamental objectives of the automotive industry today is the fuel economy; therefore, reducing vehicle weight has been pushed to the limit especially in the new body designs, without neglecting the passengers passive safety that these structures should provide. Thus, the achievement of these goals is only possible through the implementation of advanced high strength materials along with new design techniques and their associated manufacturing processes. In this investigation, a study of the implementation of three steels, categorized by the AISI, as advanced high strength steels (AHSS) in the manufacture of a cross bar is done. The results obtained are compared each other and with similarly obtained results considering a conventional high-strength steel (CHSS) possessing superior forming properties, but lower resistance properties regarding AHSS considered in this study . To this goald the foundation of the simulation process all necessary operations are presented to perform the sheet forming of a cross car for commercial vehicle floor and a comparative performance takes place between the four selected steels. A safety factor regarding the FLD curve is proposed. The use of appropriate material models of deformation processes involved in forming sheet and the correct definition of the mechanical properties associated with them are essential.