Application of Tailor Rolled Blank in Vehicle Front End for Frontal Impact 2007-01-0675

Lighter weight and lower cost have been pursued in automotive industry. Traditionally, metal sheets of uniform thickness are used for stamping or forming vehicle structural parts. For a desired structure, a metal sheet with varying thickness is desirable. It not only saves material but also increases design flexibility. For example, some areas of a cross member require thicker thicknesses to support localized, larger loading, while for other areas, where there is no localized loading, thinner thicknesses can be used to save material. Tailor Rolled Blank (TRB) is an emerging manufacturing technology which allows engineers to change blank thickness continuously within a sheet metal, virtually eliminating the need for welding local reinforcements in the part. TRB also provides simpler structural design due to smooth, rolled transitions, which prevent stress concentrations in the finished part. In addition, there is little cost penalty for multiple thickness transitions, due to the nature of the rolling process. In this research, TRB is applied to vehicle front end design for frontal impact. Advanced optimization technology is exploited to maximize the benefits of using TRB. A simplified front horn with both circular and rectangular cross section is used as an example to demonstrate the potential benefits.