Sustainable lightweighting technologies: High strength high crush efficiency extruded aluminum front rails for lightweight bodies

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This project will address the design and optimization, material selection and texture development, and manufacturing of a one-piece extruded front rail intended for mass production within mid-size cars, such as the Chevrolet Malibu, Chevrolet Impala and Buick Regal after 2017. Apart from the one-piece front rail, other outcomes include: a complete front rail design optimization that maximizes energy absorption characteristics and a new aluminum alloy that is not only perfect for extrusion, but demonstrates superior energy absorption and strength characteristics. This proposal is built around three highly integrated themes: (1) front rail design for optimized weight reduction and performance, (2) aluminum alloy development, and (3) simplified manufacturing process development. Optimized front rail design: The front rail geometry and material will be optimized for maximum performance and weight reduction. This will be achieved by increasing the energy absorption per unit mass (to improve performance) and shortening the length (weight reduction) of the front rail. Front rail lengths of less than O.Bm and a total weight reduction of 30-40% (in the front rail; compared to steel) are targeted. Alloy development: Based on the properties of 'pilot' alloy AA6063, an aluminum alloy will be developed with strength and energy absorption characteristics that are comparable to conventional steels. Once developed, several tests, such as tension, bending, compression, dome, biaxial stress tests, as well as microstructural studies using electron microscopy will be performed to characterize mechanical and physical properties of the developed alloy. Simplified manufacturing process: Extrusions, which are much more cost efficient than complex assemblies with multiple stampings, will be used to fabricate the new rails. Ultimately, this project will address the design and optimization, material selection and texture development, and manufacturing of a one-piece extruded front rail intended for mass production within mid-size cars, such as the Chevrolet Malibu, Chevrolet Impala and Buick Regal after 2017. Apart from the one-piece front rail, other outcomes include: a complete front rail design optimization that maximizes energy absorption characteristics and a new aluminum alloy that is not only perfect for extrusion, but demonstrates superior energy absorption and strength characteristics.