Abstract
The automotive industry is facing new environmental requirements that call for more stringent rules to protect the environment and reduce material and resources usage. As such, the automotive industry is in more need to reduce fuel consumption and control emissions in order to meet the new environmental requirements. One of the methods that helps in acheiving lower fuel consumption targets is weight reduction. Making cars lighter sounds plausable, but is it acheivable without affecting vehicle Safety as well as other customer demands for more comfort and better vehicle performance (Criteria that are a must in today’s stringent safety requirements and competitive environment.). The body-in-white (BIW) accounts for about 25% of the total vehicle weight, and thus it provides a great opportunity for weight reduction. However, the challenge is not only to reduce the vehicle’s BIW weight, but also to maintain competitive vehicle functionality in Safety, NVH and Durability.
The studied technologies include: Generic Body Architecture, Tailor Welded Blanks, Ultra High Strength Steel, Structural Foams, and Structural Adhesives. Each of these technologies was benchmarked in terms of weight savings, vs Safety, NVH, and Durability functionalities. The models that were used for the technology prove outs are based on generic modified Body Architecture CAE models. It was shown that the total weight savings acheived from architecture alone was 24 lb (out of 707 lb initial BIW weight, thus making the weight savings close to 3.4%). In addition, the combination of Tailor welded blanks and Ultra high strength steel has resulted in an 80 lb reduction in the BIW weight, which is close to 11.3%. Structural foams showed an effective increase in roof crush strength, and showed potential enhancement for frontal crash pulses as well as potential shortening of front ends. On the other hand, structural adhesives showed enormous NVH benefits in stiffness with as little as 1% energy absorption enhancement for crash. Thus producing the perfect method to compensate the reduced body stiffness due to sheet metal gage reduction and replacement with Ultra High strength steel. By such both safety and NVH functionalities are complemented without weight increase.
