Lightweight design of automotive front side rails with TWB concept

Due to the continuous tightening of various regulations for conserving energy and protecting the environment, the weight reduction of and automobile body becomes an increasingly important issue. In order to reduce the weight of an automobile, we have brought forward a method of replacing the simple structure with the tailor-welded blank (TWB), in which a design process is appropriately defined for a front side rail. Focusing on the thickness determination of TWB, we have deduced the constraint inequalities of strength, bending stiffness, and torsion stiffness to prevent the thickness from decreasing unboundedly due to the lightweight requirement, thus reducing the weight of the front side rail satisfying the design demands of these three factors. The full-width frontal impact simulation of the whole car after redesign in the front side rails has been performed to verify vital performances such as deformation mode, energy absorption, and acceleration. (c) 2007 Elsevier Ltd. All rights reserved.