A Design Concept for an Aluminum Sport Utility Vehicle Frame

As part of the joint government/industry Partnership for a New Generation Vehicle (PNGV), Ford Motor Company, with the support of Alcan Aluminum Corporation and The Budd Company, conducted a feasibility study of the design and high volume manufacturing of a lightweight aluminum sport utility vehicle frame. The specific objective of the study was to assess the capability of an aluminum frame to achieve equivalent performance to the 2002 Ford Explorer frame, but at a 40% weight reduction. Using Finite Element Analysis (FEA), it was determined that if a design was constrained to the same section size as the production steel frame, the maximum weight savings that can be realized by use of aluminum is approximately 20%. However, if the side rail sections between the front and rear suspension points can be modestly increased, the aluminum frame can match the production steel frame in static bending and torsional stiffness and have greater normal mode frequencies than the production steel frame. In addition, this allows for an approximate 40% reduction in weight compared to the production steel frame. Preliminary analysis also indicates an aluminum frame with the gage required to achieve the desired stiffness needed for ride, handling and NVH (noise, vibration and harshness) will probably have excellent energy absorption during frontal impacts.