9522774 Kyriakides The automotive industry is continuously seeking ways to reduce vehicle weight without compromising safety in order to increase fuel efficiency and increase payload capacity. Iron and steel account for the bulk of the total vehicle weight. Aluminum alloys with density of less than half of steel has the potential to lower vehicle weight substantially. The aerospace industry already has considerable experience in the use of aluminum. Translating that experience into automotive industry, a new body design called space frame has been developed. Aluminum alloys are extruded into tubes which are assembled into a space frame. Dimensional tolerances required on these cold formed tubes are high for ease of assembly in an automated process. One problem encountered in bending a thin walled tube is the distortion of the cross section. The current approach is to internally pressurize the tubes and by trial and error arrive at the optimum manufacturing process. In this research, the feasibility of developing a forming model to arrive at the least distortion loading path (pressure-tension-curvature) will be evaluated. Limited experimental verification of the model will be carried out. If successful, this research would lay the foundation for a closed loop control stretch forming of aluminum tubes. The automotive industry is a very large sector of the total manufacturing industry. Increase in fuel efficiency has been a driver in this industry with many concurrent benefits. Environmental benefit is one major factor with reduced emission along with lower vehicle operating cost to the consumer. While the industry has made continuous improvements towards this goal, replacement of steel by aluminum has the potential for a major reduction in vehicle weight with concurrent benefit in fuel efficiency. This cooperative industry/university research is seeking the most optimum manufacturing process to make this materials substitution an attractive option for the automotive indu stry.
