Body-in-White Reinforcements for Light-Weight Automobiles 2016-01-0399

Automotive OEMs are proactively working on vehicle light-weighting, powertrain optimization, alternate/renewable energy sources and combinations of the three to meet challenging corporate average fuel economy (CAFE) standards. Light-weighting of the body-in-white (BIW) is an obvious choice for vehicle light-weighting as this structure contributes to more than 30-35% of the total weight of a car. Changing manufacturing and assembly lines requires substantial investment. As such, OEMs are exploring short-term light-weighting strategies that do not require any major changes to the BIW. Local reinforcement for the BIW are pertinent solutions that does not require any major changes in the existing assembly lines.

This paper focuses on the development of BIW reinforcement solutions using engineering thermoplastic materials that can be mounted at appropriate locations on a vehicle’s BIW to achieve significant weight savings without compromising crash performance. Various design and material configurations - including plastic, metal-plastic and composite-plastic structural members - mounted on the BIW are evaluated through CAE studies for various crash scenarios such as high-speed frontal crashes, side impact, pole impact and rollover. The CAE studies, performed using generic vehicle models, quantify the potential weight-savings in a vehicle by either replacing the existing reinforcements using a lighter system or by incorporating additional reinforcements in the BIW by down-gauging the existing BIW. Approaches to correlate the CAE studies using component level testing and validation of generic reinforcements are also investigated. Data from all of this work indicate that the use of BIW reinforcements can achieve significant weight reduction (∼ 1.5%) in a vehicle, while also ensuring no compromise in crash performance.