Achieving Light-Weight Design of Automotive Bodies with Advanced High Strength Steels via Structural Optimization

The development of light-weight vehicles that are safe and durable has become an imperative for the automotive industry. The complexity of the vehicle design, the variety of available material grades, and the disparate needs (imposed by energy absorption, intrusion resistance, durability and stiffness) can make the search of light-weight design quite daunting and tedious. Optimization techniques, used in conjunction with CAE analyses, can be effective in arriving at a viable design by searching a wide spectrum of alternatives in the design space. Through a case study involving mass and material optimization, it is shown that utilization of advanced high-strength steels (AHSS) can be exploited judiciously to arrive at strong, stiff, and durable automotive structures. Multiple linear load cases, along with a non-linear roof crush load are considered in this study. Sizing optimization technique has been primarily used to optimize the structure in the linear domain, and advanced high strength steels were used to improve the roof crush performance of the structure with optimized gages.