Life Cycle Energy. Requirements for Selected Automotive Sheet Materials

New design factors have to be considered in the selection of materials to be used in automobiles as a result of Federal Government mandates on fuel economy requirements. As a result of higher energy costs, automobile designers in specifying materials are now considering not only the cost of substitute materials but also material weight, since lighter car weight promotes fuel economy.

Over the lifetime of a car, comparative life cycle energy use relationships were derived in this study for the three major materials used in making flat (sheet) products used in automobile manufacture: 1) steel, both carbon and high strength-low alloy, 2) aluminum, and 3) selected plastics.

This study focused on substitution of one material for another on a given sized automobile. Results are presented graphically showing weight trade-offs of one material against another in order to achieve equal life cycle energy use.